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Whirlwind Stringers PL-1-420
Mike Santarelli:
Hi Jim,
I have a bunch of the PL1-420 and haven't any issues with GFCIs. I have found them to be excellent quality. Maybe go through each one with a circuit tester?
Geoff Doane:
--- Quote from: Jim Klas on August 24, 2022, 03:32:00 AM --- With regards to the occasional GFCI trips, I was wondering if this could be a fault in my PowerCon cables. I have checked them all, nothing is ever in any wet situation, and as far as I can tell checking with an ohmmeter and an AC outlet tester indicates all cables are 100% correct.
--- End quote ---
Normally cables are pretty foolproof, but in the case of PowerCons there is one significant difference that your electrician may not have taken into account. In a normal twistlock or "edison" plug, the receptacle is the mirror image of the plug. This is convenient, because the lay of the wires inside the jacket on one end is the mirror image of the other, but this is not the case for PowerCon plugs. NAC3FCA (blue) and NAC3FCB (grey) connectors have the same pin arrangement, so if you just connect the black wire to the "L" terminal and the others wherever they most easily fit, you'll wind up swapping neutral and ground in each cable. The kicker is that your AC plug tester can't tell the difference, and will tell you its OK, but the GFCI knows the current is returning on the ground instead of neutral and will trip.
It's a bit difficult to get ohmmeter probes in the end of the PowerCons to check for continuity, so an easy workaround is to just chain all your PowerLink boxes together with the PowerCon cables. Don't plug it into an AC supply, and don't plug anything else into it. You should be able to measure continuity (very low ohms) between the chassis of any of the PowerLink boxes and any other box. If there is a swap happening, there will only be continuity between every second box in the string.
In the days before the "pin 1 problem" was addressed, this would be a recipe for copious amounts of hum in a PA system. I assume you haven't had any trouble with that, so at least the gear is working properly. :)
Or maybe it's something else totally different. :(
GTD
Steve-White:
--- Quote from: Geoff Doane on September 13, 2022, 08:27:31 PM ---Normally cables are pretty foolproof, but in the case of PowerCons there is one significant difference that your electrician may not have taken into account. In a normal twistlock or "edison" plug, the receptacle is the mirror image of the plug. This is convenient, because the lay of the wires inside the jacket on one end is the mirror image of the other, but this is not the case for PowerCon plugs. NAC3FCA (blue) and NAC3FCB (grey) connectors have the same pin arrangement, so if you just connect the black wire to the "L" terminal and the others wherever they most easily fit, you'll wind up swapping neutral and ground in each cable. The kicker is that your AC plug tester can't tell the difference, and will tell you its OK, but the GFCI knows the current is returning on the ground instead of neutral and will trip.
It's a bit difficult to get ohmmeter probes in the end of the PowerCons to check for continuity, so an easy workaround is to just chain all your PowerLink boxes together with the PowerCon cables. Don't plug it into an AC supply, and don't plug anything else into it. You should be able to measure continuity (very low ohms) between the chassis of any of the PowerLink boxes and any other box. If there is a swap happening, there will only be continuity between every second box in the string.
In the days before the "pin 1 problem" was addressed, this would be a recipe for copious amounts of hum in a PA system. I assume you haven't had any trouble with that, so at least the gear is working properly. :)
Or maybe it's something else totally different. :(
GTD
--- End quote ---
Interesting and good to know about Powercon's. Going to have to look over my cable testers and make sure they will test the Powercon stuff.
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