safety when connecting panels into strings

[RShackleford]

An old electricians trick is keep one hand in your pocket.

Similarly, wife and I wear silicon wedding rings. Me because doing lot of electrical work, she because she's a climber. Similarly, when I followed the Braves as a kid, a pitcher who'd played basketball in college was walking down the street with his teammates, and was bragging about being able to dunk; so he jumped up to do a mock dunk on an awning, it caught his ring, and tore ligaments in his hand - never fully recovered his career. Not quite as gruesome as above, but it stuck with me.

Anyhow, glad I appear to be erring on the side of too careful, instead of not careful enough, with these PV cables.

[Salts]

There are more available. I use to teach HV classes for our Power Electricians to show them what not to do. You can't believe the number of ARC flash injuries or burn deaths caused by taking the easy path.

Ya I can.. Complacency takes more victims than high cholesterol... Darwin demands his quota..

[SunEagle]

Wow.. that's a shocking picture...

There are more available. I use to teach HV classes for our Power Electricians to show them what not to do. You can't believe the number of ARC flash injuries or burn deaths caused by taking the easy path.

[Salts]

Wow.. that's a shocking picture...

[Mike90250]

An old electricians trick is keep one hand in your pocket. If your shoes are insulated and you are not leaning against something, generally you are alright, unlike this fellow:



0000978_arc-flash-safety_550.jpeg

or Sunking's Crispy Cable Thieves:

copper cable thiefs crispy.jpg
Their green handle wire cutters seem to be OK though.

[RShackleford]

So how would a solar panel complete it's circuit if one of the MC4 connectors isn't connected to anything? Remember, the current has to go back to the source, so how would current go back to the source (solar panel) if one of the MC4 connectors isn't connected to anything?

Yep, I see your point now.

[Salts]

I don't think we're really disagreeing here. Yes, you need to complete a circuit to get shocked. And standing on the ground will do it (whether it be ungrounded conductor in your house or PV wire). And yes, if you're insulated well enough from the ground, you won't get shocked.

So how would a solar panel complete it's circuit if one of the MC4 connectors isn't connected to anything? Remember, the current has to go back to the source, so how would current go back to the source (solar panel) if one of the MC4 connectors isn't connected to anything?

[RShackleford]

I don't think we're really disagreeing here. Yes, you need to complete a circuit to get shocked. And standing on the ground will do it (whether it be ungrounded conductor in your house or PV wire). And yes, if you're insulated well enough from the ground, you won't get shocked.

[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.

[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..

[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.

[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]

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.

[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]

... 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.