# Ground spike under a tire.... (Unsafe grounding practices)



## chrisf

Alright, I have no idea where this ridiculous practice came from, but I have been fighting hard against it.

Take this to your units. Take this to CFSCE. Take this the hell out of the heads of sig ops.

PUTTING A GROUND SPIKE UNDER A TIRE DOES NOTHING! NOTHING WHAT SO EVER! IT PROVIDES NO SAFE OR USEFUL GROUND! STOP DOING IT!

I don't know where the practice originated from, but for some reason, but it's quite common. Connecting a grounding cable to the grounding lug on a vehicle, laying the grounding spike behind a tire, and backing the vehicle a few inches backward to put weight on the spike... somone at some point decided that if the ground was too hard to pound in a spike (Read: The det commander is too lazy/incompetant to move their truck give feet backwards to the edge of the pavement). 

Now courtesy of the pyramid scheme that is army education, this unsafe electrical practice propogates...

Placing a ground spike on the ground under a tire accomplishes nothing, it provides functionally NO electrical conductivity between the vehicle and the ground, and thus no ground protection.

Why do you want ground protection you ask?

#1. Grounding for your electrical system, provides protection in the event a live wire comes in contact with an enclosure or somthing else electrical. Basically, keeps you from getting shocked.

#2. Lighting protection. Helps to disapate lightning to ground.

#3. Secondary grounding protection when using AC, should the bonding wire to the generator or utility supply fail.

#4. It forms half your freakin' antenna! Using half wave antenntas, no ground, and half your antenna is missing!

So please, stop this practice and start fighting against it, it's going to get people hurt.


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## PuckChaser

Proper grounding saved a few of my operators and a CP vehicle from catastrophic damage when it was hit by lightning.

Maybe one of the techs that are floating around here can answer this question: Which grounding lug is used on the LSVW? The one on the VIP or the one on the power panel? I've heard conflicting reports that one of them is disconnected.


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## SevenSixTwo

a Sig Op said:
			
		

> Alright, I have no idea where this ridiculous practice came from, but I have been fighting hard against it.
> 
> Take this to your units. Take this to CFSCE. Take this the hell out of the heads of sig ops.
> 
> PUTTING A GROUND SPIKE UNDER A TIRE DOES NOTHING! NOTHING WHAT SO EVER! IT PROVIDES NO SAFE OR USEFUL GROUND! STOP DOING IT!
> 
> I don't know where the practice originated from, but for some reason, but it's quite common. Connecting a grounding cable to the grounding lug on a vehicle, laying the grounding spike behind a tire, and backing the vehicle a few inches backward to put weight on the spike... somone at some point decided that if the ground was too hard to pound in a spike (Read: The det commander is too lazy/incompetant to move their truck give feet backwards to the edge of the pavement).
> 
> Now courtesy of the pyramid scheme that is army education, this unsafe electrical practice propogates...
> 
> Placing a ground spike on the ground under a tire accomplishes nothing, it provides functionally NO electrical conductivity between the vehicle and the ground, and thus no ground protection.
> 
> Why do you want ground protection you ask?
> 
> #1. Grounding for your electrical system, provides protection in the event a live wire comes in contact with an enclosure or somthing else electrical. Basically, keeps you from getting shocked.
> 
> #2. Lighting protection. Helps to disapate lighting to ground.
> 
> #3. Secondary grounding protection when using AC, should the bonding wire to the generator or utility supply fail.
> 
> #4. It forms half your freakin' antenna! Using half wave antenntas, no ground, and half your antenna is missing!
> 
> So please, stop this practice and start fighting against it, it's going to get people hurt.



Yea, sadly it's done all the time. I have no idea who started it but you are right it should stop. 

What should also stop is exercises in a parking lot that has no grass and just cement ;-).


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## chrisf

PuckChaser said:
			
		

> Proper grounding saved a few of my operators and a CP vehicle from catastrophic damage when it was hit by lightning.
> 
> Maybe one of the techs that are floating around here can answer this question: Which grounding lug is used on the LSVW? The one on the VIP or the one on the power panel? I've heard conflicting reports that one of them is disconnected.



Either one. 

Wherever the rumor that one or the other lug was "disconnected" came from was a load of fecal matter as well. They should be both still bonded to the vehicle chassis, if for some reason one happens to not be bonded then that's a problem with that specific vehicle.

I've demonstrated this for several unbelievers on multiple vehicle.  ("But on my QL3 course master-corproal such and such said..." "Call them and ask if they have a electrical engineering degree. If they don't, then I'm right and they're wrong.")


 If you know how to use a multimeter, borrow one from your local tech shop or line shop, and check the resistance between the two lugs, should be less than an ohm. Then check the resistance from the lugs to chassis should also be minimal. If you don't know how to use a multimeter, borrow the whole tech or lineman and have them do the same.


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## chrisf

> What should also stop is exercises in a parking lot that has no grass and just cement ;-).



We operate in an increasingly urban enviroment... people need to learn how to operate PROPERLY and SAFELY in this enviroment.

Running back to the trees won't help.


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## MrMustard

I am REALLY glad you mentioned this. Oddly enough, not more than a couple of weeks ago, I had this very discussion with a Cpl at my unit who happens to be an electronics SME. I just looked at him, looked at the ground spike (which was still neatly tucked into its scabbard on the back of the door of the LSVW) and looked at the pavement beneath us and said, "It does nothing to just plop it down behind the tire doesn't it?", to which he replied, "Absolutely nothing". 

I suppose you could argue that it is a 'driil' of sorts, and the mere act of connecting it and throwing it under a tire will help everyone remember to do it. So yes, though there is no functionality to it, good ol' muscle memory is always something to practice.


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## chrisf

MrMustard said:
			
		

> I am REALLY glad you mentioned this. Oddly enough, not more than a couple of weeks ago, I had this very discussion with a Cpl at my unit who happens to be an electronics SME. I just looked at him, looked at the ground spike (which was still neatly tucked into its scabbard on the back of the door of the LSVW) and looked at the pavement beneath us and said, "It does nothing to just plop it down behind the tire doesn't it?", to which he replied, "Absolutely nothing".



An equally good pair of questions would be why it was still stuck in the door, and why, if he was unable to ground the vehicle in that location, was he set up in that location, and why hadn't he moved the truck?



> I suppose you could argue that it is a 'driil' of sorts, and the mere act of connecting it and throwing it under a tire will help everyone remember to do it. So yes, though there is no functionality to it, good ol' muscle memory is always something to practice. does nothing.



No, you can't argue that it's a drill, if it's not grounded, it's not set up properly. That makes as much sense as encouraging people to stick their finger down the barrel of their rifle to keep the rain out (But only when it's not loaded).


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## PuckChaser

Whats the best way to ground a vehicle that HAS to be set up on a concrete pad? If damage to the grounds wasn't a concern, pounding a hole is fine. The only thing I can think of is having a long grounding cable available and run the spike out to the closest grass/dirt area.


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## Kat Stevens

If in a compound, scrounge up a jumper cable clamp and clamp it to a fence post, or any other embedded metal object.  A welder's ground clamp would be even better.


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## MrMustard

a Sig Op said:
			
		

> An equally good pair of questions would be why it was still stuck in the door, and why, if he was unable to ground the vehicle in that location, was he set up in that location, and why hadn't he moved the truck?
> 
> No, you can't argue that it's a drill, if it's not grounded, it's not set up properly. That makes as much sense as encouraging people to stick their finger down the barrel of their rifle to keep the rain out (But only when it's not loaded).



Moving the truck wasn't an option. As I said, he's a SME. He knows and he would have if he was able to, but he was not. The gigantic parade square we use as a vehicle compound did not afford him too many options within the time he had to do it in.  

Secondly, I agree with you that putting the ground spike under the tire doesn't actually do anything for grounding the vehicle. What it DOES do, is get troops into the habit of pulling it out and going through the process of connecting it etc so that they don't forget. So that it becomes automatic. Like a drill. I don't need to clear my weapon EVERY time I enter a building because with the 'soldier first' mentality, I ALWAYS know the state of my weapon. No exceptions. But it's the drill, as I've learned it, so I do it.


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## chrisf

PuckChaser said:
			
		

> Whats the best way to ground a vehicle that HAS to be set up on a concrete pad? If damage to the grounds wasn't a concern, pounding a hole is fine. The only thing I can think of is having a long grounding cable available and run the spike out to the closest grass/dirt area.



A longer cable is fine. Use the same gauge as the original spike.

As Kat pointed out, clamping to somthing else that's metal and pounbed into the ground works as well, chain link fences work well. If you're going to use a jumper cable, I'd suggest taping it after it's clamped to prevent the clamp from slipping off.


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## chrisf

MrMustard said:
			
		

> Moving the truck wasn't an option. As I said, he's a SME. He knows and he would have if he was able to, but he was not. The gigantic parade square we use as a vehicle compound did not afford him too many options within the time he had to do it in.



Define "SME"'. If he's never had to wear a flash protection suit and walk around like darth vader to turn off a breaker, then he fails to impress me.

The option is to move the vehicle to somewhere it can be suitably grounded. 

If your chain of command requires you to set up somewhere the vehicle can't be grounded you have two options. Discuss the unsuitability of the site with your chain of command, and move the vehicle, or come up with an alternate grounding method.

Caveat to all this, operating on the move, the vehicle doesn't need to be grounded, popping the antenna on for a quick comms check, not a big deal... 

HOWEVER, OPERATING in a FIXED location, if the vehicle isn't grounded you're doing it wrong, and you're asking to get hurt eventually.



> Secondly, I agree with you that putting the ground spike under the tire doesn't actually do anything for grounding the vehicle. What it DOES do, is get troops into the habit of pulling it out and going through the process of connecting it etc so that they don't forget. So that it becomes automatic. Like a drill. I don't need to clear my weapon EVERY time I enter a building because with the 'soldier first' mentality, I ALWAYS know the state of my weapon. No exceptions. But it's the drill, as I've learned it, so I do it.



So you advocate doing somthing wrong for the sake of doing it? Again, that makes as much sense as sticking your finger down the barrely of a rifle to keep the rain out. If you're going to do a drill, you do it right. Thats why it's called a drill.

If you teach people to do the wrong thing, they will continue to do that wrong thing, and teach others to do the same.


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## Franko

To alleviate some of your concerns, I've never seen the practice ever done in any CP I either visited or worked in.

Must be a new thing some moron came up with.

Regards


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## chrisf

Der Panzerkommandant.... said:
			
		

> To alleviate some of your concerns, I've never seen the practice ever done in any CP I either visited or worked in.
> 
> Must be a new thing some moron came up with.
> 
> Regards



I've seen it done many times, across Canada, mostly by inexperienced det commanders, somtimes by very experienced people.

Definitly from a moron though.


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## josh54243

On my QL3 course the ground spike had to be 2/3 in the ground or at least buried if spiking it in was not possible (and I assume this is CFSCE standards)


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## chrisf

JohnTBay said:
			
		

> On my QL3 course the ground spike had to be 2/3 in the ground or at least buried if spiking it in was not possible (and I assume this is CFSCE standards)



Yes, that's the standard, and the standard has never changed.

Yet, at some point somone somewhere decided that if you couldn't pound the spike, sticking it under a tire would suffice, and this has continued to propogate, informally, mostly among people too lazy to do it properly.


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## MrMustard

a Sig Op said:
			
		

> Define "SME"'. If he's never had to wear a flash protection suit and walk around like darth vader to turn off a breaker, then he fails to impress me.
> 
> The option is to move the vehicle to somewhere it can be suitably grounded.
> 
> If your chain of command requires you to set up somewhere the vehicle can't be grounded you have two options. Discuss the unsuitability of the site with your chain of command, and move the vehicle, or come up with an alternate grounding method.
> 
> Caveat to all this, operating on the move, the vehicle doesn't need to be grounded, popping the antenna on for a quick comms check, not a big deal...
> 
> HOWEVER, OPERATING in a FIXED location, if the vehicle isn't grounded you're doing it wrong, and you're asking to get hurt eventually.
> 
> So you advocate doing somthing wrong for the sake of doing it? Again, that makes as much sense as sticking your finger down the barrely of a rifle to keep the rain out. If you're going to do a drill, you do it right. Thats why it's called a drill.
> 
> If you teach people to do the wrong thing, they will continue to do that wrong thing, and teach others to do the same.



My SME - he's an electrical engineer. As for the site, it was a quick comms check so it really didn't matter. 

And no, I do not advocate doing something wrong for the sake of doing it. Did I say that? I related the action of setting up the ground spike as part of the drill of a det set up. OBVIOUSLY there is ONLY the correct way of doing it - which is hammering the bastard into the ground (yes, even in the Gore!) 2/3 of the way for proper conductivity. All I'm saying, is that whoever started this 'under the tire' nonsense likely did so to get troops into the habit of thinking about the ground spike, but it probably turned into what we know today as an improper function. This then, is a failure of knowledge and by virtue of that, of leadership.


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## Swingline1984

Word to the wise.  Just because you pound that pathetic 2 ft rod into the ground does not mean you have a good ground or even a ground at all.  Another bad practice is having several different points of ground, your potential should be the same across the system i.e. All points should be bonded together.  Your coax should also have a polyphaser and a sheath to ground.


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## Franko

Swingline1984 said:
			
		

> Word to the wise.  *Just because you pound that pathetic 2 ft rod into the ground does not mean you have a good ground or even a ground at all.  *Another bad practice is having several different points of ground, your potential should be the same across the system i.e. All points should be bonded together.  Your coax should also have a polyphaser and a sheath to ground.



So is that where the practice of watering the spike comes from?

Regards


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## George Wallace

Proximity to the watertable is the idea.  The spike in very (extremely) dry ground really is not that effective.........or so I believe.

Water/wet/moist ground conducts electricity, while dry ground is a poor conductor.


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## Franko

George Wallace said:
			
		

> Proximity to the watertable is the idea.  The spike in very (extremely) dry ground really is not that effective.........or so I believe.
> 
> Water/wet/moist ground conducts electricity, while dry ground is a poor conductor.



I can tell you that in another province at the FOB we had operational equipment that was checked by the techs for every conceivable technical error to the point of watering the spike with gallons of water but still couldn't get any further out than 3km. At one point we were 300m away and still couldn't raise the CP. Could have been a myriad of other effects affecting the kit. Frustrating to say the least.

Everything was done with other means. 

Regards


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## chrisf

Der Panzerkommandant.... said:
			
		

> So is that where the practice of watering the spike comes from?
> 
> Regards



Regular watering of the spike will improve conductivity to ground (Though you'd be amazed how many people don't know that's why the spike is hollow)

Radial grounds are another improvement on that.

There's other options as well, deeper grounds, grounding plates, grounding networks.


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## Swingline1984

There are also chemical grounds as well.  For radio systems there are also things called 'false' grounds, which by their very nature, mimic ground but don't provide much protection from external sources; lightning being an example.  I've heard tell from some of the older more seasoned HF operators that one practice was to use an empty beer can filled with water, the can coming from the requisite 6 pack in everyones ruck.


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## Sig_Des

I remember seeing something that I thought was pretty ingenious, that could very well be useful in the urban/parking lot set-up.

Basically it was a grounding strap designed to be plugged into any regular wall outlet, and using it's ground. No need to worry about jerry-rigging something up, just find yourself an outlet.

I'm sure others know more about the science to it, but it seems like it would be something feasible.


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## REDinstaller

Des,

Electrical Gnd is only as good as the maint of the grounding system for the electrical side. With RDS, the electrical ground acheived through the power cord is never relied on, hence all equipment is grounded to its shelf, the shelf is grounded to the rack, the rack is tied to the Main Terminal Ground used for the Bldg comms closets. This avoids ground potential, and ground loops that are common in electrical systems. It is possible that some electrical circuits ground voltage is plus or minus of zero which an ideal ground should be 0. This puts risk to personel and equipment as both are unable to tolerate a ground potential which can be as high as the higest voltage used with in that bldg. This is why the genny tlr has a ground rod, and so does the veh hooked up to it.


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## chrisf

Terrible idea on the outlet. It's one of those "knowing just enough to be dangerous". There's way too much impedence to ground.

There's a difference between grounding and bonding. Grounding is the direct connection to the earth, bonding is what connects everything else to the ground. The "ground" in an outlet is not actually a ground, it's "bond".

The absolute bare minimum of the grounding conductor (Meaning the actual connection to ground) for a standard CP rad truck would be 8AWG, that's from the Canadian Electrical Code (CEC), I'm guessing the actual standard as dictated by the military is probably higher.

The bonding wire you'd be plugging into, if it's a normal outlet, is 14AWG. Not nearly sufficient safe grounding.


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## REDinstaller

The ground is provided by the ground plug on an outlet. Bonding is the mechanical action where by enough tension is applied to 2 surfaces of an similar material (copper to copper) that allows the maximun surface contact to be achieved. This removes ground loops and false or intermittent readings when grounds are tested.


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## chrisf

Straight from the code...

Bonding - A low impedence path obtained by permanently joining all non-current-carrying metal parts to ensure electrical continuity, and having the capacity to conduct safetly any current impsed on it.

Ground - A connection to earth obtained by a grounding electrode.

I realise it sounds like I'm trying to play a game of symantics here, I'm really not. 

I'm not arguing with you per-say, as we're both saying the same quite the same thing, that grounding is important, and critical for safety, but these are the *electrical* definitions of bonding and grounding, and cause confusion quite regularly, even with electrical professionals.

A "bond" does not constitute a "ground" because as you pointed out, a bond may fail, or may not actually be connected to ground. Any point up until the spike itself is arguably a bond. A bond does not become grounded until (And straight from the code here) it is "connected effectively with the general mass of the arth through a grounding path of sufficiently low impedence, and having an ampacity sufficient at all times, under the most severe conditions liable to arise in practice to prevent any current in the gorunding conductor to prevent harmful voltage to exist".

The 14AWG bonding wire in a standard 15A electrical outlet is NOT sufficient to to provide connection to ground a standard rad truck. 

I don't remember the max current rating of the standard power connection for a CP vehicle, but I do know for sure it's not more then a hundred amps. That being said, the minimum *ground* would be 8 AWG

My point with all this is that just because it's bonded doesn't make it grounded. The 14AWG bonding wire in a 15A outlet isn't even sufficient to bond it.

Far too often, especially with sig ops in my experience, it's again an issue of a little knowledge being a dangerous thing.

Example being the "cheater"plug Beadwindow 7 was referring to. Somone (definitely a sig op) knew they need to ground things for safety and comms. They know that the electrical system of a building is grounded. What they didn't know is that plugging into an outlet was not sufficient for a safe ground.


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## REDinstaller

a Sig Op said:
			
		

> Straight from the code...
> 
> Bonding - A low impedance path obtained by permanently joining all  metal parts to ensure electrical continuity, and having the capacity to conduct safely any current imposed on it.
> 
> Ground - A connection to earth obtained by a grounding electrode.
> 
> I don't remember the max current rating of the standard power connection for a CP vehicle, but I do know for sure it's not more then a hundred amps. That being said, the minimum *ground* would be 8 AWG
> 
> My point with all this is that just because it's bonded doesn't make it grounded. The 14AWG bonding wire in a 15A outlet isn't even sufficient to bond it.
> 
> Far too often, especially with Sig ops in my experience, it's again an issue of a little knowledge being a dangerous thing.
> 
> Example being the "cheater"plug Beadwindow 7 was referring to. Someone (definitely a Sig op) knew they need to ground things for safety and comms. They know that the electrical system of a building is grounded. What they didn't know is that plugging into an outlet was not sufficient for a safe ground.



That is why TBITS is the Communications installation standard for the CF. The max current for LSVWs would be the lowest rating in the veh power system. The power cable is just a long fuse when you push too much current through it.

When TCI's for Comms Systems are performed, we examine the Communications Grounds very closely. That's why power cables aren't a reliable ground. We can't verify where they are jumpered or terminated. Grounding the power cable is only for power, the ground lug on the patch panel is for the comms system protection.


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## Swingline1984

With regards to inside plant we bond to ground mainly for EMI.  The Telecommunications Main Building Ground (TMBG) is tied back to one of the following:  building structure, closest electrical panel, main building ground, and in some older buildings the water main; which in all cases are tied together.  This is, as you stated, to avoid differences in potential between the systems, preventing one system, through isolation, from using another as a pathway to ground at a point where they accidentally become common (usually structure).  In outside plant we bond to ground for high voltage i.e. Lightning.  The outside plant is fused to ground at it's entry point to a building.  It is also at this point the cable is no longer shielded and therefore the pathway (tray or EMT) acts in this capacity.  In RDS installations they take it a step further and either use fibre optic or STP for horizontal cabling.  The smallest ground cable used in a Telecom installation is usually 6AWG unless your looking at a frame and then it is 12AWG.  Don't get me started on antenna systems which run the gammit from huge buried ground screens, which are part of the array, to large flat ribbons to provide maximum surface area to disperse lightning strikes.  If you want some fun stories talk to some of the older Linemen about molecular bonds.


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## chrisf

Tango18A said:
			
		

> That is why TBITS is the Communications installation standard for the CF.



TBITS?


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## Occam

a Sig Op said:
			
		

> TBITS?



TBITS 6.9, to be precise.

http://www.tbs-sct.gc.ca/it-ti/itp-pti/its-nit-eng.asp


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## chrisf

Ah. (To reiterate the original point of the thread, I suspect "just stick your spike under a tire" is not included)


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## Swingline1984

TBITS is a "standard".  Standards are flexible except where they point to Code.  Code is law.


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## REDinstaller

Swingline1984 said:
			
		

> TBITS is a "standard".  Standards are flexible except where they point to Code.  Code is law.



And the code is the Canadaian Electrical Code, pertaining to electrical service.


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## Swingline1984

Tango18A said:
			
		

> And the code is the Canadaian Electrical Code, pertaining to electrical service.



Not nessesarily.  You must adhere to whichever is the more stringent.  In some cases that is Provincial Code i.e. Ontario Electrical Code etc.


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## REDinstaller

This is true as well. I know that in Quebec, all the rubber coating must removed of flex conduit prior to its installation in any bldg.


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## Sig_Des

a Sig Op said:
			
		

> Far too often, especially with sig ops in my experience, it's again an issue of a little knowledge being a dangerous thing.
> 
> Example being the "cheater"plug Beadwindow 7 was referring to. Somone (definitely a sig op) knew they need to ground things for safety and comms. They know that the electrical system of a building is grounded. What they didn't know is that plugging into an outlet was not sufficient for a safe ground.



Thanks to T18A and others for explaining the science besided it.

A Sig Op...The strap I saw was actually the brainchild of an LCIS, but thanks for the trade-wide assumption of incompetence. I know that as of late you have something of a self-loathing towards the trade, and yes, there are idiots, but please don't generalize.

You've known me what, 6-7 years now? Yeah, I'll cut corners, but not with the safety of my det.


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## chrisf

Beadwindow 7 said:
			
		

> A Sig Op...The strap I saw was actually the brainchild of an LCIS, but thanks for the trade-wide assumption of incompetence. I know that as of late you have something of a self-loathing towards the trade, and yes, there are idiots, but please don't generalize.



It's wasn't meant as an accusation of trade wide incompetence, but I appologise, as I can understand why you took it that way. 

That being said, me being fed up with the trade doesn't come into it. Sig Ops don't get any electrical training, beyond basic safety and operation of small generating equipment. This includes a bit of theory. Unfortunately, a little knowledge being a dangerous thing, and people start tinkering with things that should be left to professionals. 

While in fairness, this isn't limited to sig ops, it extends to anyone with a little basic knowledge of electricity and more importantly, access to electricity (Farmers and your typical home owner are common examples). I recently observed a light switch installed in somones home, wired with two pieces of CAT5 cable. Sig ops however, regularly meet those two criteria of having a bit of knowledge (Simple electrical theroy) and access to power (generators).

Fair enough, it was made by an LCIS tech, that doesn't make it safe, it's still dangerous, and shouldn't be used. Too much impedence to ground. Whoever made it wasn't familiar with proper and safe grounding practices. Unfortunately, they handed it off to somone who assumed that since it was made by an LCIS tech it was ok.


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## MOOXE

How do you test your ground?


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## LineJumper

With a ground megger


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## MOOXE

Would the LCIS/FCS shops carry one of those?

I would really be interested to know if a ground spike under a tire does ABSOLUTLEY nothing.


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## chrisf

They should. They're also used for testing insulation. They might not want to lend it to you, they're lovely devices for shocking the unwary (It's like an ohmeter, only much higher voltage, most test at 600V and 1000V), but ask them to demonstrate it to you.

Compare the earth connection with the spike under the tire on ashphalt to a spike pounded into dirt.


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## Swingline1984

MOOXE said:
			
		

> I would really be interested to know if a ground spike under a tire does ABSOLUTLEY nothing.



It is as good a ground as the guy leaning against the truck smoking is.  I don't know about you but I would prefer if my troops were not the path of least resistance.  An earth megger is standard kit in a Line shop.


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## chrisf

If you question it in the slightest, I would encourage you to find the equipment to test it and demonstrate it... and do it in front of other people... if we can stamp out this ridiculous practice, that would be fantastic...


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## bleating_goat

Hi everyone,

I know this is a stupid question, but I'm going to be teaching a class on electrical safety, and I'd much rather look like an idiot here than in front of my class.  :blotto:  Basically, I'm wondering whether it's safe to touch the ground spike.  I have always been told that it's not, and one of the safety principles on this old lesson plan I'm going off of is "Never touch the ground spike!"  But, it was my understanding that a ground spike simply provides a pathway to transfer excess electrical charge from the equipment into the ground, and that consequently, touching the ground spike would be no worse than touching the equipment itself.  Am I just missing something here?

Thanks for any answers you can provide!


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## George Wallace

To me this is like asking the question whether or not it is safe to hold onto the antenna when someone transmits.  It is not safe.  Electricity will find the path of less resistance.  That could land up being you.


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## chrisf

The ground spike connects the vehicle to the ground (earth, point of zero potential).

Provided the spike firmly pounded, and ground wire is properly connected, there is little to no danger in touching it, is a much lower resistance path to earth than you are. 

It's when there's a fault in the system somwhere you've got a problem. 

If there's a break in the path of the grounding connection, happens frequently at the nut which attaches the spike to the wire, then there is potential for shock, as you may become the ground. That being said, if there is a break in the break in the grounding connection, exactly the same danger is present from touching ANY part of the now ungrounded vehicle as from touching the grounding wire (Ever been shcocked from a vehicle with a bad ground you try to climb onto it? It's unpleasent, and this is why, you're providing a path to earth)

It's slightly different from touching a transmitting antenna, as the antenna itself ungrounded, it has no path to ground. Say for example you're standing on a metal vehicle shelter roof, or on the deck of an AFV. Either one of those things will a different potential than the transmitting antenna, on touching the antenna, current will travel through you to the point of lower potential.

End result, the result of danger from touching a ground spike is about same as the danger in touching a vehicle itself.


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## Occam

Regarding touching a transmitting antenna;  while it's possible you might get a shock from a transmitting antenna, it's likely to be a high voltage/low current shock, which will wake you up but not injure you.  The concern about touching a transmitting antenna is the RF burn you'll likely receive, which will hurt like a regular burn.  At higher transmitting powers, you don't even need to be touching the antenna to receive a burn...much like being microwaved.  Not pleasant!


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## chrisf

I was going to paste a link to the wikipedia article on electric shock, but it's really badly written. Really really badly written. Even by wikipedia standards.

I would love to know who produced the flaming hot dog pic though.

Oh, and bleating goat, check your private messages (Should be a link at the top of the page).


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## Occam

a Sig Op said:
			
		

> I would love to know who produced the flaming hot dog pic though.



You're probably too young to remember these.  You had prongs on either side of the carrier, and you pushed a hot dog onto the prongs.  Cooked via electric current...they worked well, too.  PETA probably got them banned for being cruel and inhumane to weiners...   ;D


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## chrisf

Anything that awesome was definitly before my time. 

We both know that PETA had nothing to do with the ban, at some point, somone definitly looked at it, unzipped their pants, etc, and then no more hot dog cookers.

I had a few scanned from some OLD (Turn of the last century) electrical code books a while back... I've heard stories of "old timer" electricians using their fingers to check for voltage, and being able to tell you how much was there by how it felt... one of these books explains how to check for voltage with your fingers, and suggests an alternative method of building a voltage tester if you weren't manly enough take the pain... another suggested that a quick finger up the rectum was the best method for reviving somone from electrical shock...


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## Occam

a Sig Op said:
			
		

> another suggested that a quick finger up the rectum was the best method for reviving somone from electrical shock...



That's what chicken sticks were for.


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## chrisf

I'm confused, is it used to cook chickens, or is it wedged up a rectum, or both? I hope they washed it in between....


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## Occam

a Sig Op said:
			
		

> I'm confused, is it used to cook chickens, or is it wedged up a rectum, or both? I hope they washed it in between....



Wedged up the rectum of people who got zapped because they didn't discharge large capacitors prior to working on the circuit, which is what the chicken stick is _supposed_ to be used for.   ;D


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## chrisf

I once watched a man with a screw driver taped to the end of a wooden broom stick short circuit a capacitor about as big as a family sized soup can... I'm not sure if it was appropriate to laugh, but the look of sheer terror in his eyes just made it funny at the time.

I couldn't find the original scan, but I found a quote from the pages... (Disclaimer: Don't do this at home kids. Call an electrician. If you absolutely have to mess about with electricity, and refuse to get a professional, master-craft meters are usually on sale for $20 at Canadian tire.)


"The American Electricians Handbook (1942) A Reference Book for Practical Electrical Workers. Terrell Croft, consulting engineer. McGraw Hill Book Company, Inc, New York and London 1942


Electricians often test circuits for the presence of voltage touching the conductors with the fingers. This method is safe where the voltage does not exceed 250 and is often very convenient for locating a blown-out fuse or for ascertaining whether or not a circuit is alive. Some men can endure the electric shock that results without discomfort whereas others cannot. Therefore, the method is not feasible in some cases. Which are the outside wires and which is the neutral wire of a 115/230 volt three wire system can be determined in this way by noting the intensity of the shock that results by touching different pairs of wires with the fingers. Use the method with caution and be certain that the voltage of the circuit does not exceed 250 before touching the conductors.


159. The presence of low voltages can be determined by testing. The method is feasible only where the pressure is but a few volts and hence is used only in bell and signal work. Where the voltage is very low, the bared ends of the conductors constituting the 2 sides of the circuit are held a short distance apart on the tongue. If voltage is present a peculiar mildly burning sensation result, which will never be forgotten after one has experienced it. The taste is due to the electrolytic decomposition of the liquids on the tongue which produces a salt having a taste. With voltages of 4 or 5 volts, due to as many cells of a battery, it is best to test for the presence of voltage by holding one of the bared conductors in the hand an touching the other to the tongue. Where a terminal of the battery is grounded, often a taste can be detected by standing on moist ground and touching a conductor from the other battery terminal to the tongue. Care should be exercised to prevent the 2 conductor ends from touching each other at the tongue, for it they do a spark can result that may burn."


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## chrisf

Found them.


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## Occam

Makes me glad I'm trained in the late 20th century!


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## RADOPSIGOPACCISOP

a Sig Op said:
			
		

> The ground spike connects the vehicle to the ground (earth, point of zero potential).
> 
> Provided the spike firmly pounded, and ground wire is properly connected, there is little to no danger in touching it, is a much lower resistance path to earth than you are.
> 
> It's when there's a fault in the system somwhere you've got a problem.
> 
> If there's a break in the path of the grounding connection, happens frequently at the nut which attaches the spike to the wire, then there is potential for shock, as you may become the ground. That being said, if there is a break in the break in the grounding connection, exactly the same danger is present from touching ANY part of the now ungrounded vehicle as from touching the grounding wire (Ever been shcocked from a vehicle with a bad ground you try to climb onto it? It's unpleasent, and this is why, you're providing a path to earth)
> 
> It's slightly different from touching a transmitting antenna, as the antenna itself ungrounded, it has no path to ground. Say for example you're standing on a metal vehicle shelter roof, or on the deck of an AFV. Either one of those things will a different potential than the transmitting antenna, on touching the antenna, current will travel through you to the point of lower potential.
> 
> End result, the result of danger from touching a ground spike is about same as the danger in touching a vehicle itself.



This is not quite true. The ground spike is still dangerous when dealing with large currents (such as from a short circuit, wire or lightning strike).

The issue comes from the fact that impedence and resistance in a conductor can increase when the conductor comes under high currents. A good analogy for electricity and conductors is that of wires and pipes. A ground spike, with a 8 gage wire, is a rather large pipe for electricity. However if the current is large enough, the "pipe" might not be enough to allow all that current to flow smoothly. If you grab the ground spike, you become an alternate source of grounding, which electricity might use, should the main ground be less than ideal to deal with the current. You, in effect, be come part of a grounding array.

In short, while the ground spike, in good working order and properly installed, might be sufficent for general radio use if you are touching it, should a unusual amount of current be sent to ground, you may be putting yourself up as ONE of the paths of least resistance.


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## REDinstaller

It also means that if you are touching any part of the truck and the ground you are at the same risk. The insulating properties of the tires only work if you are fully in/on the truck, otherwise you are acting as a secondary grounding point. This is why we use a ground spike, otherwise the veh would retain the voltage.


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## chrisf

RADOPSIGOPACCISOP said:
			
		

> This is not quite true. The ground spike is still dangerous when dealing with large currents (such as from a short circuit, wire or lightning strike).



While I'll be the first to admit, I make plenty of mistakes, for this, it's 100% true. In case you're wondering, this is "what I do".

Please understand, I don't mean this as a insult, but this is again what I referred to earlier as a little knowledge being a dangerous thing. I'm trying very hard to fight against a few commonly held misconceptions about electricity I've seen repeatedly in the signals world, this is one of them. Several of these misconceptions, such as the ground spike under the tire, are extremely dangerous, and I'm trying very hard to end them before someone is injured.

Any time in a person in a position of any authority unintentionally passes on any of these misconceptions, its very hard to remove them at a later time. (I'm still wary of eating water melon seeds for fear a water melon may grow in my belly).

Contrary to popular belief, current does not "travel through the path of least resistance". Current travels through all paths to the point of lower potential (voltage) at all times. The less resistance, the more current that travels through that path.

In low voltage systems, under a thousand volts, current through insulation is negligible, so we typically ignore it.

In higher voltage systems, with more parallel insulator surface, say, underwater transmission cables, current through insulation is large enough to note, for power loss and safety. The majority of the current travels through the conductor core, however, a small minority of current travels through the insulation to ground.

With regards to a grounded vehicle, if the truck is at a higher potential than the earth, then current will flow to the earth. This is why we pound a ground spike, to give a low resistance path for the majority of current to flow.

If you happen to touch the truck, and earth at the same time, if the truck is grounded properly, some current will flow through you, some will flow through the grounding electrode (spike). Under normal conditions, nearly all will flow through the spike. Some will flow through you, a tiny tiny tiny amount will flow through the vehicles tires, and some will flow through the air.

If the truck is not grounded properly, and you touch it, more current will flow through you, the amount depending on your connection to earth. If you're standing on dry pavement, not much will flow through you. If you're kneeling in wet dirty, more will flow through you.

Under fault conditions, such as a lightning strike, there will be a great deal more current. Further, the voltage present in a lightning strike will break down resistance in insulators. If the vehicle is properly grounded the majority of that current will flow through the spike, some current will flow through the tires, and some will flow through the air. If you happen to be touching any part of the vehicle, or even standing close to the vehicle, some of that current will flow through you to ground.

Proper actions on lightning should also have the operator remove their headset, and wait for the storm to end. A set up should also not be attempted during a lightning storm.

For maximum safety, installation of the ground spike should be the first thing done on set up, or at least prior to operation of any electrical equipment or installation of antennas. If I remember correctly, the first two things done in a "normal" set up of  a3 man LSVW rad det are installation of the ground spike and placement of the drip pan, prior to anything else.

(If you want further reading, http://www.lightningsafety.com/nlsi_pls/vehicle_strike.html as an added bonus if you read the article, you'll get to dispel the myth about rubber tires insulating you during a lightning strike)


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## Edward Campbell

a Sig Op said:
			
		

> Alright, I have no idea where this ridiculous practice came from, but I have been fighting hard against it.
> 
> Take this to your units. Take this to CFSCE. Take this the hell out of the heads of sig ops.
> 
> PUTTING A GROUND SPIKE UNDER A TIRE DOES NOTHING! NOTHING WHAT SO EVER! IT PROVIDES NO SAFE OR USEFUL GROUND! STOP DOING IT!
> 
> I don't know where the practice originated from, but for some reason, but it's quite common. Connecting a grounding cable to the grounding lug on a vehicle, laying the grounding spike behind a tire, and backing the vehicle a few inches backward to put weight on the spike... somone at some point decided that if the ground was too hard to pound in a spike (Read: The det commander is too lazy/incompetant to move their truck give feet backwards to the edge of the pavement).
> 
> Now courtesy of the pyramid scheme that is army education, this unsafe electrical practice propogates...
> 
> Placing a ground spike on the ground under a tire accomplishes nothing, it provides functionally NO electrical conductivity between the vehicle and the ground, and thus no ground protection.
> 
> Why do you want ground protection you ask?
> 
> #1. Grounding for your electrical system, provides protection in the event a live wire comes in contact with an enclosure or somthing else electrical. Basically, keeps you from getting shocked.
> 
> #2. Lighting protection. Helps to disapate lightning to ground.
> 
> #3. Secondary grounding protection when using AC, should the bonding wire to the generator or utility supply fail.
> 
> #4. It forms half your freakin' antenna! Using half wave antenntas, no ground, and half your antenna is missing!
> 
> So please, stop this practice and start fighting against it, it's going to get people hurt.




This is a very interesting and very useful thread. Thanks, a Sig Op for starting it.

Much of the discussion over four pages has focused on items 1 and 2. During the last 1/2 of my career I had a great deal to do with radios: big, fixed radios and radars; little handhelds, shipborne rigs and pretty much everything that radiated. I want to add some emphasis to Item 4: your radio (or radar or whatever sort of emitter) is, broadly, only as effective as the antenna and, as a Sig Op said, proper grounding is a major factor getting the signal "through." Grounding can often be a big problem: ask any sailor or airborne system designed or anyone who has served in a desert.

That fact that getting a proper ground can be hard does not mean that it cannot be done; it can be done - in nearly 20 years I never saw/heard of a problem our experts could not solve (given enough money) - and, indeed, it must be done if you professional Signals people are going to do your jobs. If you do find it too hard, ask: ask the Foreman of Signals, ask a smart officer (some are, you know ... really, I'm not kidding), if they cannot help ask them to ask the _geeks_ and _nerds_ in Ottawa.


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## RADOPSIGOPACCISOP

a Sig Op said:
			
		

> While I'll be the first to admit, I make plenty of mistakes, for this, it's 100% true. In case you're wondering, this is "what I do".
> 
> Please understand, I don't mean this as a insult, but this is again what I referred to earlier as a little knowledge being a dangerous thing. I'm trying very hard to fight against a few commonly held misconceptions about electricity I've seen repeatedly in the signals world, this is one of them. Several of these misconceptions, such as the ground spike under the tire, are extremely dangerous, and I'm trying very hard to end them before someone is injured.
> 
> Any time in a person in a position of any authority unintentionally passes on any of these misconceptions, its very hard to remove them at a later time. (I'm still wary of eating water melon seeds for fear a water melon may grow in my belly).
> 
> Contrary to popular belief, current does not "travel through the path of least resistance". Current travels through all paths to the point of lower potential (voltage) at all times. The less resistance, the more current that travels through that path.
> 
> In low voltage systems, under a thousand volts, current through insulation is negligible, so we typically ignore it.
> 
> In higher voltage systems, with more parallel insulator surface, say, underwater transmission cables, current through insulation is large enough to note, for power loss and safety. The majority of the current travels through the conductor core, however, a small minority of current travels through the insulation to ground.
> 
> With regards to a grounded vehicle, if the truck is at a higher potential than the earth, then current will flow to the earth. This is why we pound a ground spike, to give a low resistance path for the majority of current to flow.
> 
> If you happen to touch the truck, and earth at the same time, if the truck is grounded properly, some current will flow through you, some will flow through the grounding electrode (spike). Under normal conditions, nearly all will flow through the spike. Some will flow through you, a tiny tiny tiny amount will flow through the vehicles tires, and some will flow through the air.
> 
> If the truck is not grounded properly, and you touch it, more current will flow through you, the amount depending on your connection to earth. If you're standing on dry pavement, not much will flow through you. If you're kneeling in wet dirty, more will flow through you.
> 
> Under fault conditions, such as a lightning strike, there will be a great deal more current. Further, the voltage present in a lightning strike will break down resistance in insulators. If the vehicle is properly grounded the majority of that current will flow through the spike, some current will flow through the tires, and some will flow through the air. If you happen to be touching any part of the vehicle, or even standing close to the vehicle, some of that current will flow through you to ground.
> 
> Proper actions on lightning should also have the operator remove their headset, and wait for the storm to end. A set up should also not be attempted during a lightning storm.
> 
> For maximum safety, installation of the ground spike should be the first thing done on set up, or at least prior to operation of any electrical equipment or installation of antennas. If I remember correctly, the first two things done in a "normal" set up of  a3 man LSVW rad det are installation of the ground spike and placement of the drip pan, prior to anything else.
> 
> (If you want further reading, http://www.lightningsafety.com/nlsi_pls/vehicle_strike.html as an added bonus if you read the article, you'll get to dispel the myth about rubber tires insulating you during a lightning strike)



Chris, 
I understand what you are saying, which is what I am saying as well, except I didn't want to get into the nuts and bolts of it as well.  All things said, touching the groundspike is dangerous, because current will travel through any path. Perhaps I was simplifying things by saying "least resistance" when I should have said "low resistance". Current will travel through any path of sufficently low resistance for the particular voltage of the circuit. Being essentially a bag of water, our happy Sig Op is a path of low resistance. So he will feel the effects of his share of the current based on the diffential of the resistances of him and the primary path.


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## chrisf

No, we're not saying the same thing. 

Provided SOPs for vehicle set-up and operation are followed, touching the ground spike is no more dangerous than any other part of the vehicle, which in turn is safe under normal conditions when used with proper grounding. 

Fault conditions, like lightning, are an entirely different bag of tricks, as discussed above. Lightning will quite happily arc through the air if it feels like it, no touching anything required. This is why we have a whole set of safety SOPs for lightning.


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## SevenSixTwo

Had an argument recently about ground spike needing to be grounded. Needless to say they just setup the generator on dry pavement and put the ground spike underneath the tire.


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## chrisf

The worst part about this is you can't even rely on Darwinism. It's likely not the twat who put the ground spike under the tire who's going to get shocked.

Further notes on unsafe grounding practices, because I've seen this one done a few times as well, tossing a ground spike into a snow bank, or pounding it into snow will not provide an effective ground either. Snow is an extremely poor conductor of electricity. Spike still needs to be pounded into the earth.


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