Questions on Generac 6852 setup with Lightning

[intensifi]

It’s a meter collar that incorporates an automatic transfer switch. The only utility offering them is PG&E in California as far as I know.

What he said!

Currently being manufactured by Tesco.

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[Jhawks9028]

I spent $3k to install the Generac panel, and then remove it. My licensed electrician could not get it to work while being in code. In fact, we smoked a wall box when the Generac panel allowed power from the main bus and truck simultaneously. Trying to bypass ground to avoid GFCI faults is hazardous. Until something changes, I’m back to a portable generator for the house.

 

[RickLightning]

I contacted Global Power Products who sells GenerLink. They told me that my utility soon should be approved for the product. They would not provide any other information, including cost, but said they thought it would be a monthly charge.

My utility is known for monthly charges. That won't fly with me.

Edit - Since my utility never responded to my emails, I called them today. Turns out they have the GenerLink with whole house surge. $50 installation and $22.99 per month. Way too pricey.

 

[CyclopsThere]

I spent $3k to install the Generac panel, and then remove it. My licensed electrician could not get it to work while being in code. In fact, we smoked a wall box when the Generac panel allowed power from the main bus and truck simultaneously. Trying to bypass ground to avoid GFCI faults is hazardous. Until something changes, I’m back to a portable generator for the house.

I try this week with some good electricians. Fingers crossed....

 

[DesertEV]

I spent $3k to install the Generac panel, and then remove it. My licensed electrician could not get it to work while being in code. In fact, we smoked a wall box when the Generac panel allowed power from the main bus and truck simultaneously. Trying to bypass ground to avoid GFCI faults is hazardous. Until something changes, I’m back to a portable generator for the house.

This is great info. Thanks for sharing.

 

[chl]

Thank you both for the replies.

As a follow up question, I think one point where I may be confused about is how the PPO is connected to the home’s grounding system.

I think part of my confusion is that I have in my mind that since the home’s neutral and ground are bonded, when the 6852 switches to generator, both neutral and ground are swapped to the generator; in other words I have in my mind that the 6852 isolates it’s 8 circuits from the home’s ground when it switches to generator. I am now gathering that this is not correct, but rather both the generator and the home are always tied to a common ground bus in the 6852. If it’s the latter, then I can see that the trucks PPO is tied to the home’s ground through the ground wire in the cord. Can you help me confirm my understanding on this?

The transfer switch switches the hots and neutral, the ground is not switched. The ground is continuous.

The neutrals of the house circuits the transfer switch switches are isolated from the breaker panel neutral grounding, since they are grounded to the lightning ground.

The point is to only have the neutrals grounded at one point, in this case to the Lightning ground.

If the neutrals were grounded at the Lightning (by the lightning bonding of the neutral to the ground) AND also grounded at the house panel (by the house panel bonding of the neutral to the ground) then there could/would likely be a voltage differential resulting in a small current differential on the current carrying conductors, which will appear to be a ground fault current and trip the GFCI in the Lightning.

The ground wires absolutely still need to be grounded to the house ground, so the ground wires are all connected. A ground fault is in essence a disconnected or high resistance ground path and without GFCI, could cause death or serous injury.

When connected this way, the Lightning ground wires are connected to the house and utility grounding, one or more ground rods generally located near the service to the house.

Grounding is needed for more than just protecting from thunderstorm lightning. It protects a human in the case where there is a metal frame/case, in a drill for example, that comes into contact with a current carrying conductor. The ground wire provides a path to ground. Without the ground wire, if the human is touching the now 'hot' frame/case and touches anything grounded, or has wet feet and is standing on the ground or other conducting surface, then current will flow through the human to ground.

A GFCI circuit detects whether the current flowing TO the drill for example on the hot wire is the same as the current coming back FROM the drill on the neutral wire. If it is not the same within say 5 milliamps, then the GFCI quickly opens the circuit cutting off the flow of electricity to the drill. The detected current difference could be because of a human path to ground, so the GFCI protects the human from a continuous flow of current through them that could be injurious.

However, when the neutral is grounded in two places, there is a second path through ground for some part of the current from the source to flow. So the current on the HOT wire at the Lightning GFCI circuit and the current on the NEUTRAL wire will not be the same, and the GFCI will trip.

In simple terms, if the neutral is bonded in two places, there will be a second path for the neutral current to flow, through ground, and the TO and FROM currents will be different.

 

[chl]

I try this week with some good electricians. Fingers crossed....

If wired correctly, the transfer switch will switch the hots and the neutrals on the circuits powered by the Lightning, while the grounds are continuous. The result is the neutrals in the circuits in question are grounded in one place by the bonding of neutral to ground in the Lightning, and the GFCI will not trip due to a second current path (unless there is a real ground fault of course).

A properly functioning transfer switch disconnects the circuits from the utility source BEFORE connecting them to the generator/Lightning source.

If it is a manual transfer switch, the switch that goes from LINE to GEN is a double-throw switch to accomplish the disconnect before connect function.

The transfer switch whether manual or automatic would have to have been wired wrong to send power from both the line/utility and the Lightning at the same time!

The line hot wire to a house circuit breaker is bypassed through the transfer switch double-throw LINE/GEN switch when wired properly, making it impossible to have both line/utility and gen/Lightning current provided simultaneously.

 

[CyclopsThere]

If wired correctly, the transfer switch will switch the hots and the neutrals on the circuits powered by the Lightning, while the grounds are continuous. The result is the neutrals in the circuits in question are grounded in one place by the bonding of neutral to ground in the Lightning, and the GFCI will not trip due to a second current path (unless there is a real ground fault of course).

I had to read this post like 5 times to start to understand Someday I'll get smart, but not today. I'm saving it to show to the electricians if they start to say that they can't do the job.

 

[Henry Ford]

I spent $3k to install the Generac panel, and then remove it. My licensed electrician could not get it to work while being in code. In fact, we smoked a wall box when the Generac panel allowed power from the main bus and truck simultaneously. Trying to bypass ground to avoid GFCI faults is hazardous. Until something changes, I’m back to a portable generator for the house.

Thay seems like an unusually difficult install. Is there something specific about your house that made it so difficult? Is it very old?

 

[chl]

I had to read this post like 5 times to start to understand Someday I'll get smart, but not today. I'm saving it to show to the electricians if they start to say that they can't do the job.

If they say that, find some other electricians who are competent to install a transfer switch!

I have a master's degree in Computers and Electrical Engineering, but most of my knowledge of home wiring, grounding, breaker panels, etc., comes from reading the NEC codebooks over the years, carefully.

We have three utility sheds in our backyard wired for electricity. The first is a shed for my wife to do pottery in - I did not want a kiln in my basement. I hired an electrical installation company to do that one - it did not go well. First, they cut my buried phone and internet lines digging the trench from the house to the shed, even though they had been warned they were there. Second, they wired the shed such that one of the two hot leads was connected to the neutral terminal in the breaker box in the shed. I plugged in a drill to a 120vac outlet and it got smoked. Why I wondered? A volt meter showed 240vac at the outlet. Checking the wiring of the breaker box I found the issue. Third, they did not pull a permit and get the required inspection, so 20 years later, when a nasty neighbor called the County about our sheds, and they came, they looked it up and cited me for not having gotten a permit. Fourth, 25 years after the installation, one of the outlets stopped working intermittently and the circuit breaker popped now and then too. Oddly, the when the outlet was dead and the breaker was set, there was no continuity from the breaker box to the outlet on the hot lead - that is, the hot wire had a break in it somewhere. I had to open the wall to trace the problem to a wire staple that had been pounded in with too much force to a 2x4 that, over time, with heating and cooling from carrying current, had cause a break in the hot lead and now and then a short circuit popping the breaker. Luckily the breaker prevented a fire from starting.

From that experience, I learned that just because someone is a licensed electrician does not mean they are competent and never make mistakes.

So when we put up the second and third sheds, I did the wiring myself, carefully following the NEC code and the local code provisions, pulled permits and had inspections which all passed.

One thing in the code that I took note of was the issue of bonding the neutrals.

With out buildings/sheds having sub-panels, the neutrals shall not be bonded at the sub-panel.

I was curious as to why the neutral would not be bonded in the sub-panel, and read up on the subject where I learned that if the neutral is bonded/grounded in two separate places, like the house and an out building, part of the return current on the neutral will flow through the ground which is undesirable and can create a shock hazard under certain conditions.

In the case where the circuit is a GFCI protected circuit, the difference in the current in the hot wire and the current in the neutral (because some is going to ground) will be detected as a ground fault and trip the GFCI device.

That is what can happen with the Lightning GFCI protected 240vac outlet if the neutral is not switched in the transfer switch along with the hot wires when you power your house from the Lightning outlet.

Good luck!

 

[GDN]

..... The truck will probably struggle to power most AC units though due to the start current. Anything much over 1.5 ton will probably require a 25-30 A breaker and will pull significantly more on startup. There are soft start units that might help. If you have a small inverter based mini-split you might be OK.
.......

Don't hesitate to try your AC. The truck can power many of them as long as you add a soft start and don't still try to run the whole house at once. From my experience up to a 4 ton should be doable and even a super-efficient 5 ton.

In TX in July I'd gladly turn most everything off to get the AC to run.

I bought and added the ASY-368-X72-BLUE from Micro-Air. I am just short being able to start my 5-ton unit. From the factory my 5-ton needs something like 140 amps to start. With the soft start it brought it down to 36 amps. @ 240 volts that is 8640 watts. The truck won't give that, but it is close. There is a report on the ICE forum of a 5 ton unit with the soft start being run form Pro Power.

 

[hturnerfamily]

I received an email the other day from GENERLINK, out of Atlanta, and pursued an email conversation back-and-forth about whether their 'Meter Base Adapter' would work with my Georgia Power Utility.
NO.

Now, this is not that it won't work for the Lightning, necessarily, but each Utility has to APPROVE of it's installation and usage within their own utility equipment/grid limitations or compatibility.

But, they then sent me a link to a 'new, not yet released' product, which they proclaim as a 'switch-panel' of sorts that ANY utility will allow.
So, I asked them the ultimate question: does it work with the LIGHTNING's Bonded Neutral?
NO. I does not. Therefore, no, it still will not work with BONDED generators, like our LIGHTNING.

Ford Lightning MANUAL
Grounding Type Neutral Bond:
The neutral of the inverter generator is bonded to system ground.
Connecting loads that also have neutral bonded to ground causes
the ground fault detection to trip.

 

[CyclopsThere]

OK the generac is in a very conspicuous place on the wall, bigger than i expected, and we solved the ground fault issue. They announced it worked, everything I looked at was working, and I signed the papers and we're done.

Then I start playing, running some scenarios. The gas furnace won't turn on, on heat mode, ONLY when it's being powered by the truck. When the power is switched over to the utility it works again. I called the electricians to solve this, since heating in a power outage is the primary reason for going thru all this stuff.

Any thoughts?

 

[Henry Ford]

OK the generac is in a very conspicuous place on the wall, bigger than i expected, and we solved the ground fault issue. They announced it worked, everything I looked at was working, and I signed the papers and we're done.

Then I start playing, running some scenarios. The gas furnace won't turn on, on heat mode, ONLY when it's being powered by the truck. When the power is switched over to the utility it works again. I called the electricians to solve this, since heating in a power outage is the primary reason for going thru all this stuff.

Any thoughts?

It sounds like power isn't getting to the furnace for some reason. A gas furnace is very low amperage. Check for voltage at the furnace when on truck power.

Thinking while typing... maybe some part of the safety circuit is on another circuit which is not on the Generac panel. My knowledge in this area is very limited but you could test this theory by shutting off circuits associated with the furnace (a/c, etc) and seeing if the furnace works.

 

[CyclopsThere]

Here's more details I sent to the electricians this morning. They've been very responsive-- If you're in this area I'd be happy to pass their info along to anyone via DM. Shit happens when we all try something new, so I'm not feeling blame-y.


The furnace is a Trane XR 80 gas furnace. I wouldn't expect it to draw too much power or need too high peak power to spark the gas.

I've been doing everything with the following process to "ease into" the heater starting just to remove variables:

1. Turn OFF the furnace & system via nest
2. Wait for all fans to stop, if they're still going
3. Turn OFF the furnace breaker
4. Switch the power source to/from grid/generator
5. Turn ON the furnace breaker
6. Turn ON the heat mode of the furnace, set the temp 5 degrees higher than house
7. Thermostat reads heating no matter the power source.

With the Generac switched to GRID power, the following happens:

1. The furnace fans turn on
2. Furnace lights
3. After a minute, the home fans turn on
4. Heat from vents

With the Generac switched to Generator power, the following happens

1. IF I turn on the home fans manually, those run
2. About 80% of the time, the furnace fans don't turn on. 20% of the time, they turn on for a second, then shut down.
3. If I don't manually turn on the home fans, those stay silent (furnace isn't running)

On Generator power, the refrigerator runs normally, even with all of this going on.

The truck isn't reading high load from the 240v outlet at any point

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