GFCI portable adapter question

[rhamblin]

I was recently asked to procure some Portable GFCI's for the maintenance department. So I went online found some that were small easy to use and bright yellow, and I ordered enough for everyone to have one. A few weeks later one of the maintenance guys pointed out that this device can't be used on a lot of our machines because the receptacles are not located more than 30 feet from the panel. In reading the fine print on the packaging sure enough it reads "30 feet of wire needs to be between the panel and the GFCI". So I emailed tech support because I don't see why a minimum distance would make any difference at all. They didn't really help, "Hi Robert, This GFCI has a UL rating for type 3 surge protector. Type 3 can’t be installed at the panel. The assumption is that there is certain length of wiring between the device and the power panel. UL picked 10m ( 30s feet) and we are required to mark it on the product."

Does this requirement make sense to anyone else, and can you explain it in better terms?

Recently someone from corporate brought up questions about GFCI receptacles. And of course the use of Power Tools, and extension cords, which led me to purchasing the aforementioned device. The device was a Southwire 1460013-6.

Thanks for any help in advance.

 

[user 100]

I was recently asked to procure some Portable GFCI's for the maintenance department. So I went online found some that were small easy to use and bright yellow, and I ordered enough for everyone to have one. A few weeks later one of the maintenance guys pointed out that this device can't be used on a lot of our machines because the receptacles are not located more than 30 feet from the panel. In reading the fine print on the packaging sure enough it reads "30 feet of wire needs to be between the panel and the GFCI". So I emailed tech support because I don't see why a minimum distance would make any difference at all. They didn't really help, "Hi Robert, This GFCI has a UL rating for type 3 surge protector. Type 3 can’t be installed at the panel. The assumption is that there is certain length of wiring between the device and the power panel. UL picked 10m ( 30s feet) and we are required to mark it on the product."

Does this requirement make sense to anyone else, and can you explain it in better terms?

Recently someone from corporate brought up questions about GFCI receptacles. And of course the use of Power Tools, and extension cords, which led me to purchasing the aforementioned device. The device was a Southwire 1460013-6.

Thanks for any help in advance.

There have been a couple of threads about why the 30 ft (don't bother asking why UL picked 30 ft, I have no idea) is needed for a type 3 surge protector- iirc, it has to do with the resistance of the wiring in relation to a surge- IOWs the more conductor/distance betwixt the service and the spd, the less of a hit the spd takes.....
I think.....

 

[kwired]

If you are only seeking GFCI protection - any surge protection it offers is just a bonus.

They only want some conductor between the panel and the device so there is some resistance in the conductor to help lessen the surge before it hits the SPD in the device. If you already have SP anywhere on the service this also helps.

If you get a fairly direct lightning strike it may blow up the device even if you had 100 feet of conductor to the panel.

 

[rhamblin]

There have been a couple of threads about why the 30 ft (don't bother asking why UL picked 30 ft, I have no idea) is needed for a type 3 surge protector- iirc, it has to do with the resistance of the wiring in relation to a surge- IOWs the more conductor/distance betwixt the service and the spd, the less of a hit the spd takes.....
I think.....

So why are we concerned about surge protective device, I'm technically only concerned with the ground fault protection, right?

 

[rhamblin]

If you are only seeking GFCI protection - any surge protection it offers is just a bonus.

They only want some conductor between the panel and the device so there is some resistance in the conductor to help lessen the surge before it hits the SPD in the device. If you already have SP anywhere on the service this also helps.

If you get a fairly direct lightning strike it may blow up the device even if you had 100 feet of conductor to the panel.

im not too concerned about a direct lightning strike. I'm thinking we have TVSS for that purpose. So, the concensus is that a surge could damage the gfci part of the device, thus requiring 30 feet of conductor to limit said surge?

 

[kwired]

im not too concerned about a direct lightning strike. I'm thinking we have TVSS for that purpose. So, the concensus is that a surge could damage the gfci part of the device, thus requiring 30 feet of conductor to limit said surge?

That is mostly my conclusion. You are supposed to test the device when you use it anyhow. And portable GFCI's are supposed to trip upon power loss anyway, so you do have to reset it every time you plug it in.

 

[user 100]

I'm technically only concerned with the ground fault protection, right?

IDK- are you?

You're the one who bought the equipment.:lol:

Do you feel that the extra protection is necessary?

And bear in mind what kwired said above when thinking about a surge damaging the gfci..........

 

[hbiss]

im not too concerned about a direct lightning strike. I'm thinking we have TVSS for that purpose. So, the concensus is that a surge could damage the gfci part of the device, thus requiring 30 feet of conductor to limit said surge?

I'm not sure of that. The surge protection would be ahead of the gfci so electrically that could not happen. However if the surge protection devices are located on the same circuit board or in close proximity to the gfci section, damage could occur since MOVs tend to self destruct and the resultant arcing and flame can cause collateral damage.

That said, I can't find any literature on the device you bought. Southwire doesn't seem to list them. I don't know why they would make a portable gfci with surge protection anyway.

-Hal

 

[rhamblin]

I don't know why they would make a portable gfci with surge protection anyway.

-Hal

I guess that was my original thinking.


Sent from my iPhone using Tapatalk

 

[don_resqcapt19]

.... And portable GFCI's are supposed to trip upon power loss anyway, so you do have to reset it every time you plug it in.

I don't think that is a requirement for portable GFCIs. All of the older ones did that, but none of the newer ones do.

 

[GoldDigger]

I don't think that is a requirement for portable GFCIs. All of the older ones did that, but none of the newer ones do.

AFAIK if was a UL requirement, not NEC. Possibly the motive being that after a disconnect and reconnect event that might also have involved incidentally stressing the electronics you would have to do a self-test before putting it into service again.

 

[kwired]

AFAIK if was a UL requirement, not NEC. Possibly the motive being that after a disconnect and reconnect event that might also have involved incidentally stressing the electronics you would have to do a self-test before putting it into service again.

My understanding had always been that with a cord and plug connected assembly you have a greater risk of having poor connection and should you have the ungrounded conductor connected but not the ungrounded - you have no power to the GFCI controls, but still have high risk of shock hazard from the ungrounded conductor. By designing it to need to see 120 volts before it will reset, and to trip whenever 120 volts is lost, you will greatly eliminate the risk of being shocked by anything connected to the load side of the device should you lose one of the two conductors.

Permanently wired GFCI's wouldn't see this condition nearly as frequently as portable ones might.

 

[don_resqcapt19]

My understanding had always been that with a cord and plug connected assembly you have a greater risk of having poor connection and should you have the ungrounded conductor connected but not the ungrounded - you have no power to the GFCI controls, but still have high risk of shock hazard from the ungrounded conductor. By designing it to need to see 120 volts before it will reset, and to trip whenever 120 volts is lost, you will greatly eliminate the risk of being shocked by anything connected to the load side of the device should you lose one of the two conductors.

Permanently wired GFCI's wouldn't see this condition nearly as frequently as portable ones might.

The portable devices do open the circuit where there is an open line side neutral. With the older design, they just used a line side relay, and with that design, you had to reset after each power loss. The newer ones still have open neutral protection, but do not require a reset after power loss. I am not sure how they make that circuit work, but none of them that I have bought in the last 8-10 years require reset after power loss.

 

[kwired]

The portable devices do open the circuit where there is an open line side neutral. With the older design, they just used a line side relay, and with that design, you had to reset after each power loss. The newer ones still have open neutral protection, but do not require a reset after power loss. I am not sure how they make that circuit work, but none of them that I have bought in the last 8-10 years require reset after power loss.

I haven't bought a portable device in several years and wasn't aware of the changes to them.