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Extra wire on MC240 GFCI

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Does anyone know what the extra (light gauge red) wire on the the MC240's GFCI is for? I'm sort of assuming it's some sort of remote control line, but I can't find any information on it. It connects to the pilot board.
 
I guess you've opened yours. I have yet to see the inside of one of those. Could you post some pictures? It may help getting you some answers.

That being said, let's speculate!

High power GFCI do not have built-in contactors (unlike the 120V GFCI outlets commonly used in houses). Maybe this is the control signal that energizes a contactor located on the main board. I'm currently building my own EVSE as a learning exercise. Its overall design is very similar to the MC240: compact and portable. In the design phase, I quickly came to the conclusion that by using a secondary small relay located along the GFCI sensor control wire on its way to the main contactor, I only needed one contactor. The relay is controlled by the J1772 state machine, running in a micro-controller.
A further refinement would be to replace the off the shelf GFCI sensor by a coil and an amplifier, feeding its signal into the micro-controller. This would save the need for a second relay and significantly reduce the size of the EVSE...
 
I've done a lot more than just open mine..... I hijacked the Tesla cable/connector to create a J1772 adapter, hijacked the pilot circuit to make my Spare Mobile Connector operate at 240V and all that is left is the GFCI. I have a use for that as well, but I need to understand what the extra low current red wire is for.

Here's a link to the specs and what it looks like. The model number is PGFS-23105-184, but the specs don't show any application data.

PGFS-23105 datasheet, Pinout ,application circuits 30 Amp Permanent Series (Splice-In) GFCI/ELCI
 
Found an ever better link from North Shore Safety's site:

http://www.nssltd.com/pdf/30%20Amp%20Perm.pdf

According to their table, this particular model does not have fault output notification. Yet the red wire definitely was connected to the pilot board. It doesn't really matter at this point because I think I've determined that the extra wire is for fault notification. I was sort of hoping it was some sort of external trip line which would have been useful for me to use it as a sort of 240V relay.
 
Does it look just like this? :
PGFS-23105.JPG
 
Does anyone know what the extra (light gauge red) wire on the the MC240's GFCI is for? I'm sort of assuming it's some sort of remote control line, but I can't find any information on it. It connects to the pilot board.

IIRC. The extra red wire is a 240v control for the contactor inside the gfi. The pilot board uses this signal to turn on/off the 240v to the car.
 
IIRC. The extra red wire is a 240v control for the contactor inside the gfi. The pilot board uses this signal to turn on/off the 240v to the car.

That's what I was hoping it might be for, but I see nothing in the spec sheet regarding it. Do you know what sort of control stimulus you apply to this line in order to call for the contact closure? If I remember right (I don't have the gfci in front of me right now) the unit has 2 line inputs and 2 line outputs. So I would sort of presume that the only natural thing to expect would be that applying ground to the red control might close the relay? That would be a pretty simple way for the device to work, as it would just require a 120V relay coil inside.

Do you know Scott?