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[Eric Vogel]

Excellent!  Thanks so much.  I'm assuming when I disassemble that I will find the wiring between the blue and grey end to be removable so I can thread it all back through the hole and reconnect the wires?

The only change I would consider to that approach is altering the cord on the power supply.  It is county school board equipment and we don't want to be responsible for any modifications.  I'll look at creating a pig tale with a Powercon plug on one end and a female edison on the other.  Do the reverse for the outgoing direction.

Also don't think its possible to tie on to the power supply chasis for ground.  What I'm thinking about doing is putting a receptical box after the Powercon inbound connectors with a GFCI outlet.  Power supply plugs in to that and I'll ground the case elements there as well.

Yes, the box is wired with female faston connectors.

FYI.... your PDU *may* or *may not* have a mains input that has shunt style surge suppression and EMI/RFI filters.  This type of asymmetrical load on the load side of a GFCI outlet *may* nuisance trip the GFI breaker under certain conditions.  This call is up to you, I however would not use a GFCI outlet feeding a PDU with clamped and filtered mains - just use a normal 15 or 20amp duplex.

[Lyle Williams]

Yes, the box is wired with female faston connectors.

FYI.... your PDU *may* or *may not* have a mains input that has shunt style surge suppression and EMI/RFI filters.  This type of asymmetrical load on the load side of a GFCI outlet *may* nuisance trip the GFI breaker under certain conditions.  This call is up to you, I however would not use a GFCI outlet feeding a PDU with clamped and filtered mains - just use a normal 15 or 20amp duplex.

Nuisance trips can be a problem for you guys.  Down here we trip at 30mA instead of 6mA (at twice the voltage too)

Even if you don't perform with the GFCI, initial operation of an amateur-wired box through a GFCI outlet is wise if you are doing no other verification of correct build.

[Eric Vogel]

Nuisance trips can be a problem for you guys.  Down here we trip at 30mA instead of 6mA (at twice the voltage too)

Even if you don't perform with the GFCI, initial operation of an amateur-wired box through a GFCI outlet is wise if you are doing no other verification of correct build.

NEMA (UL943) vs. IEC
https://www.nema.org/Products/Documents/NEMA-GFCI-2012-Field-Representative-Presentation.pdf
see page 4

[Lyle Williams]

RCDs at 30mA are madatory in many situations here.  If we had the "safer" 6mA standard the level of nuisance trips would have prevented them from being made mandatory. 

30mA is so much safer than the 150,000mA fault current that promptly trips a 20A breaker.  6mA is only safer if you are willing to use it.

[Stephen Swaffer]

RCDs at 30mA are madatory in many situations here.  If we had the "safer" 6mA standard the level of nuisance trips would have prevented them from being made mandatory. 

30mA is so much safer than the 150,000mA fault current that promptly trips a 20A breaker.  6mA is only safer if you are willing to use it.

This true; however, IMO, better to use it and avoid buying products that create nuisance trips.  Raise the bar of expectations from manufacturers and demand gear that can be used safely-even when GFCI use is called for. Refrigeration equipment used to be considered incompatible with GFCI-now GFCI protection is mandatory on a lot of refrigeration-if the market demands it, they will figure it out.

[Eric Vogel]

A note regarding using GFCI's for portable cord connected equipment and portable power distribution...

It may be tempting to install any one of several high quality units listed here:

http://www.hubbell-wiring.com/Press/PDFS/H5212.pdf

However, if you intend to feed any of these outlets with portable cordage, you risk injury or death if the 'cordage' develops an open neutral with a line faulted and a possible open EGC... the GFCI will not trip at all under this condition, and the closed loop of fault current thru your body will likely not exceed the threshold current of the OCD feeding this branch circuit.  The circuit will stay hot until unplugged - very dangerous.

A better solution is to feed your portable loads with something like part number GFP15M from here (page 4):

http://ecatalog.hubbell-wiring.com/press/pdfs/H5004.pdf

The key to safely inserting GFCI protection into schemes with 'portable cordage' is OPEN NEUTRAL PROTECTION - without this, a normal GFCI can kill you when fed with cordage that is faulty - no better than a normal duplex outlet.

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24542

[Gary Christenot]

A note regarding using GFCI's for portable cord connected equipment and portable power distribution...

It may be tempting to install any one of several high quality units listed here:

http://www.hubbell-wiring.com/Press/PDFS/H5212.pdf

However, if you intend to feed any of these outlets with portable cordage, you risk injury or death if the 'cordage' develops an open neutral with a line faulted and a possible open EGC... the GFCI will not trip at all under this condition, and the closed loop of fault current thru your body will likely not exceed the threshold current of the OCD feeding this branch circuit.  The circuit will stay hot until unplugged - very dangerous.

A better solution is to feed your portable loads with something like part number GFP15M from here (page 4):

http://ecatalog.hubbell-wiring.com/press/pdfs/H5004.pdf

The key to safely inserting GFCI protection into schemes with 'portable cordage' is OPEN NEUTRAL PROTECTION - without this, a normal GFCI can kill you when fed with cordage that is faulty - no better than a normal duplex outlet.

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24542

How about plugging this on to the power cord  supplying the cart power between the male end of the cord and the venue provided AC outlet.

[Eric Vogel]

How about plugging this on to the power cord  supplying the cart power between the male end of the cord and the venue provided AC outlet.

I would use it near or next to your rack - creating a safe zone, sort of...

so from venue outlet > whatever extension cords > GFP15M > short cord plugged into your rack

Also you can keep an eye on the status of the GFCI right at the rack, and handy for operating the test button once everything is hooked up.

[Gary Christenot]

I would use it near or next to your rack - creating a safe zone, sort of...

so from venue outlet > whatever extension cords > GFP15M > short cord plugged into your rack

Also you can keep an eye on the status of the GFCI right at the rack, and handy for operating the test button once everything is hooked up.

Thanks again Geoff.  Yes, I see the utility in that arrangement.  The only draw back is he ordered/purchased a prefabbed 50' cord with male Edison on one end and Powercon plug on the other.  So the only way to get the GFCI next to the rack would be to cut the Powercon connector off a couple feet shy of the end, then on the two bare ends install a female Edison on the long section, and a male Edison on the short section.  We're definitely trying to stay with unaltered, off-the-shelf stuff as much as possible.

But it seems to me that having it near the AC outlet end of the cord would actually be safer.  If it was near cart, and there was a short in the cord connecting to the house power outlet somewhere between the outlet and the GFCI, would the GFCI trip in that situation? 

This stuff is going to be manhandled by high school goods being loaded off and on trailers, rolling across parking lots, out on to football fields, etc.  Seems to me I would want the GFCI as close to the AC source as possible so that as much of the whole system - cords and all - that is between the outlet and the kids is GFCI protected.

Gary 

[Eric Vogel]

Thanks again Geoff.  Yes, I see the utility in that arrangement.  The only draw back is he ordered/purchased a prefabbed 50' cord with male Edison on one end and Powercon plug on the other.  So the only way to get the GFCI next to the rack would be to cut the Powercon connector off a couple feet shy of the end, then on the two bare ends install a female Edison on the long section, and a male Edison on the short section.  We're definitely trying to stay with unaltered, off-the-shelf stuff as much as possible.

But it seems to me that having it near the AC outlet end of the cord would actually be safer.  If it was near cart, and there was a short in the cord connecting to the house power outlet somewhere between the outlet and the GFCI, would the GFCI trip in that situation? 

This stuff is going to be manhandled by high school goods being loaded off and on trailers, rolling across parking lots, out on to football fields, etc.  Seems to me I would want the GFCI as close to the AC source as possible so that as much of the whole system - cords and all - that is between the outlet and the kids is GFCI protected.

Gary

You can certainly use it at the source outlet, keeping your existing cabling intact.

Just keep an eye on people wanting to push the test button 'out of your sight'.

-Eric

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