Spd300 ac sends volts thru from ac out to ac in?

[Vic]

Good point boB & Ryan,  on the missing Neutral/Ground Bond.   I had missed that.

The thing that I do not really understand,  is doing wiring in that panel with any AC circuits powered.

We all have wired things HOT,  but would bet that anyone doing that is going to be very,   very,     very careful,   and knew well,   just which parts were HOT.

IMO,     Vic

[boB]

Good point boB & Ryan,  on the missing Neutral/Ground Bond.   I had missed that.

I noticed there wasn't a specific connection for the bond I think but assumed they were connected.

The thing that I do not really understand,  is doing wiring in that panel with any AC circuits powered.

What I do not understand is why our documentation would say to wire the L1 and L2  LOAD/OUTPUT side to an SPD ??

And especially, the SAME SPD for input and output if one wants to do that if there is an L2 to be dealt with ??  There MAY be a good reason for that though that I am not thinking of right now.

Lighting has a much higher probability of hitting the grid side than the inside of the house I would think.

You can protect the inside of the house though of course and it shouldn't hurt....  OR tingle  ! 

[FNG]

Realize even a Magnum inverter can run voltage between neutral and ground with no bond as they are floating, I have been bit by that one in the past

[boB]

Yes, these products have small-ish capacitors from L1 and L2  to  GND for their common-mode filtering.

That's usually where the AC leakage comes from without anything else like an SPD connected.

But you would normally see about half the AC line voltage between L1 and GND.

If GND and Neutral are tied together it might be different.

[The Ugly One]

The thing that I do not really understand,  is doing wiring in that panel with any AC circuits powered.

What it was I did all the wiring inside the panel when it was dead. I didn't power up the inverter yet. It was dark and it was time to put the house ac line from generator plug to the panel. So I unplugged the house from generator. Took the plug off the wire. Wired the house into the system. Had the line for the ac-in to inverter already wired in to the panel. Had the spd already wired in. Because there was people inside without power I turned on the power. Keeping in mind that there was no more wiring to be done inside the panel. I had the ac-in breaker turned off. So to my knowledge there was no reason for my ac-in wire to have any power what so ever and now all I needed to do is put the plug end onto the ac-in to inverter wire so I could plug in the generator to send power to the inverter from generator. And while wiring the plug end to the plug that is when the spark started. And after that point I tested it with the meter and it still carried 90v from positive-negative of the live-in wire. It stayed with power up until the point where I disconnected the spd... I did all my work without power into the box or panel. My breaker that might allow back feed of power was turned off. The thing that allowed power to pass thru the system to the line that shocked me was the connection inside the spd. So in my mind the spd was faulty and it put me into the situation of being hurt/injured. (My pride is hurtn I am not hurt.) So i should of said from the get go in better wording how i was working. Is their a true schematic of the spd that we can look over to see what may of done this? I would disassemble the unit but I want to get a replacement if it was truly defective.

[boB]

The thing that I do not really understand,  is doing wiring in that panel with any AC circuits powered.

What it was I did all the wiring inside the panel when it was dead. I didn't power up the inverter yet. It was dark and it was time to put the house ac line from generator plug to the panel. So I unplugged the house from generator. Took the plug off the wire. Wired the house into the system. Had the line for the ac-in to inverter already wired in to the panel. Had the spd already wired in. Because there was people inside without power I turned on the power. Keeping in mind that there was no more wiring to be done inside the panel. I had the ac-in breaker turned off. So to my knowledge there was no reason for my ac-in wire to have any power what so ever and now all I needed to do is put the plug end onto the ac-in to inverter wire so I could plug in the generator to send power to the inverter from generator. And while wiring the plug end to the plug that is when the spark started. And after that point I tested it with the meter and it still carried 90v from positive-negative of the live-in wire. It stayed with power up until the point where I disconnected the spd... I did all my work without power into the box or panel. My breaker that might allow back feed of power was turned off. The thing that allowed power to pass thru the system to the line that shocked me was the connection inside the spd. So in my mind the spd was faulty and it put me into the situation of being hurt/injured. (My pride is hurtn I am not hurt.) So i should of said from the get go in better wording how i was working. Is their a true schematic of the spd that we can look over to see what may of done this? I would disassemble the unit but I want to get a replacement if it was truly defective.

If there was no power connected in or out of the SPD or box, I am not sure why you would feel anything ?  There are no power sources inside the SPD itself.


HOWEVER, there is a 1.0 mA  (or so) current source circuit in there to light up the blue LED or LEDs.  Depending on the SPD model, the center of the LED current source circuit may or may not be connected to the center green GND wire.  The LED circuit requires at least 10V input (AC or DC) to work (approximately)

I would need FNG  to reply to this too though as he/she/it  would know better than I would which version you have.

BUT with NO input or output circuits on, there should not be any voltage source.  Are you certain that the AC breakers are good ?

[ClassicCrazy]

I was hooking up an SPD on my combiner box outside and when I touched the box the LED lit up . That was when I realized something wasn't grounded right  somewhere.

Larry

[boB]

I was hooking up an SPD on my combiner box outside and when I touched the box the LED lit up . That was when I realized something wasn't grounded right  somewhere.

Larry

If the LED lit up then it had to be that LED current source.   That may not require the GND so probably DID come through from the opposite HOT wire.  Some SPDs don't draw current for the LED through the GND wire.   The reason for that is that some PV grid tie inverters will trip their ground faults when the see any current that is going to GND and not returning through the opposite hot wire.

The current limit is around 1 mA as I remember

[mike90045]

At night, my Classic backfeeds power to the combiner box and my SPD LED glows all night

[ClassicCrazy]

The LED is always lit at my combiner box too - I thought it was supposed to be.

Larry

[Kent0]

I just took a SPD300AC off the shelf and confirmed less than 1 mA current flowing from line to ground. That small current illuminates the LED and is enough to cause someone a a mild shock. Current flowing from L1 through to L2 with the ground disconnected was very small and probably would not cause a perceptible shock. Also observed, using a Fluke 111, nearly 120 volts to ground on both the ground wire and on the L2 wire when only L1 is connected to power.

So the OP's observed shock at the generator power inlet cord must have happened because the neutral/ground connection was open.

So this event is a good reminder to turn the power off before working in the panel. I believe that in the E-panel instructions.