safety when connecting panels into strings

[bcroe]

There is enough generation from the back side of my panels to be dangerous. That is
one reason AC outdoor outlets are mounted on my array frames, for the lights and everything
else. Bruce Roe

[J.P.M.]

So you're saying that unless I acquire a (presumably expensive) fully-opague tarp like the tenters used, I'm better off with the cheap brown tarps than the cheap blue ones ? I think even that will be a pain though; I think I'll just do it in the dark; a good floodlight out there seems easier and cheaper.

No, I'm not. I'm simply reporting in good faith what my experience has been with respect to the apparent opaqueness of various tarping materials.

What you do with it, if anything, is for your engineering judgement to determine. It's simply information. Take it FWIW.

[RShackleford]

There is enough generation from the back side of my panels to be dangerous.

Meaning, from bright lights one might put underneath the frame, to assist in wiring the panels ?

That is one reason AC outdoor outlets are mounted on my array frames, for the lights and everything
else.

Not following (how generation from backside of panels suggests mounting AC outdoor outlets on array frames).

[RShackleford]

No, I'm not. I'm simply reporting in good faith what my experience has been with respect to the apparent opaqueness of various tarping materials.

Geez man, this isn't a court of law. How about "you're suggesting ..." ?

[bcroe]

The AC outlets power my night work flood lights. The light intensity of these is far
too low to generate dangerous solar panel energy. Bruce Roe

[RShackleford]

Having really looked at those MC4 connectors for the first time, I feel better. Seems pretty safe to:

1. Turn off DC connection to inverter, however that is done for your setup - built in to inverter, separate breaker or switch, whatever.
2. Do all non-MC4 connections first (that involve handling bare wire, such as into terminal blocks.
3. Don't work when it's at all wet.
4. Work during twilight.

[J.P.M.]

post was held in moderation, released now

R.U.A.

Thank you.

J.P.M.

[Salts]

I always leave one of the MC4 connectors between panels in each string open. This way, when I'm stripping wires and installing connectors, the circuit is open and I can't get shocked.

Make sure the DC switch to the inverter is off, then wire up the DC pos and neg lines into the inverter. The last thing I do before flipping the DC Switch to the ON position is to go back in the string and connect that MC4 connector I left open.

Turn on the AC, turn on the DC.

I did mine under full sunshine. No tarps or cardboard required.

[RShackleford]

... the circuit is open and I can't get shocked.

Thanks for the pointers. But as a point of order, just because the circuit is open and no current can flow, you can still get shocked - when a little bit of current flows through your body.

[Salts]

Thanks for the pointers. But as a point of order, just because the circuit is open and no current can flow, you can still get shocked - when a little bit of current flows through your body.

No. Not unless the Laws of Physics temporarily cease to govern our universe. Electrons flow from the negative terminal to the positive terminal. Without a path to come full circle back to the source, no shock can occur.

This is why helicopters can work on 100 kilovolt transmission lines while they are operating.. it is also why birds can land on a wire and not get fried.

[RShackleford]

This is why helicopters can work on 100 kilovolt transmission lines while they are operating.. it is also why birds can land on a wire and not get fried.

Bird and helicopters fly.

[SunEagle]

Thanks for the pointers. But as a point of order, just because the circuit is open and no current can flow, you can still get shocked - when a little bit of current flows through your body.

You will get shocked only if you are grounded or touching a lower voltage potential point then what the panel wiring is producing. You need to complete the circuit or a shock and spark should not be created.

Oh and birds do not get shocked while sitting on a single wire because they are not creating a circuit. It is not because they can fly.

[RShackleford]

You will get shocked only if you are grounded or touching a lower voltage potential point then what the panel wiring is producing. You need to complete the circuit or a shock and spark should not be created.

The ground is a likely a different potential (lower or higher would do it). Ever accidentally touch the ungrounded conductor in your house wiring ? You didn't need to also be touching neutral or ground to get shocked.

Oh and birds do not get shocked while sitting on a single wire because they are not creating a circuit. It is not because they can fly.

The point is, since they can fly they do not have to have their feet on the ground.

[Salts]

The ground is a likely a different potential (lower or higher would do it). Ever accidentally touch the ungrounded conductor in your house wiring ? You didn't need to also be touching neutral or ground to get shocked.

The point is, since they can fly they do not have to have their feet on the ground.

The reason you get shocked when touching the ungrounded (hot) conductor in your home is because YOU become the path back to ground. Stand on a fiberglass ladder and you can grab that conductor with your lips and not feel anything. YOU ARE THE PATH to ground, which is why you get shocked. Eliminate your path to ground (fiberglass ladder), and no shock.

This is Electrical 101 stuff..

[SunEagle]

The ground is a likely a different potential (lower or higher would do it). Ever accidentally touch the ungrounded conductor in your house wiring ? You didn't need to also be touching neutral or ground to get shocked.

The point is, since they can fly they do not have to have their feet on the ground.

Well actually touching the ungrounded conductor without touching with a lower potential or ground will not shock you. I know I have done it many times but I was wearing insulated boots.

Again without completing a circuit the higher potential voltage has no where to go.

I do understand about the birds though. But have you seen a kite string bridge two power line conductors? That is a very visual site to see.