Will this sub panel work?

[kuips]

Hey all,

So my electrician is saying the square d panel qogp3p6036p with a manual transfer switch should work based on what I described as being the needs for this truck. Can anyone confirm this will work?

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[Calvin H-C]

Yes and no.

We built our house in 2003 with a similar (but smaller) Square D QO transfer panel so critical circuits could be powered from a generator when needed. Worked great and we even converted our generator to natural gas for lower cost operation with no need to refuel every 8 hours.

With my wife's Lightning, we could just plug into its Pro-power as it has the same connection. Besides, it will sure beat having to start the generator in cold inclement weather.

However, the Lightning has its own GFCI protection (as it should) and simply plugging it into the inlet that we use for the generator will trip the GFCI protection. This is because the ground and neutral must be bonded together at the main panel AND ONLY at the main panel. Electricity will use every path available to it, and since the ground and neutral are bonded together in the main panel, any load current from the Lightning that the neutral must carry will be split between the neutral and the ground wires.

GFCI works by measuring the current in the hot and neutral wires to make sure what goes out on one wire comes back on the other (for a 240 V GFCI, it has to compare the two hots and the neutral to make sure everything balances out). If some current can't be accounted for, the GFCI opens the circuit because the missing current might be passing through a person.

There are two ways to prevent this.

The preferred way is to use a transfer switch that not only switches the two hot wires, but also the neutral. That way, there is never a connection between the Lightning's neutral and your house's neutral coming from the main panel.

The other way is to isolate the ground connection from the Lightning. Simply put, the ground pin on the inlet is not connected to anything. The box/housing of the inlet is still grounded by the house ground, just with no connection to the truck's ground. If this is done, the inlet should be labelled to indicate the ground connection is isolated.

You should discuss this with your electrician. They may not have been aware that the Lightning has its own GFCI protection (some generators do as well) and requires the neutral separation. If going with a new installation, I would suggest using a transfer switch that switches the neutral.

 

[chl]

From what I gather, most modern transfer switches will switch the neutrals as is needed to prevent the Ford GFCI from detecting a ground fault and opening, but good to have the electrician double-check.

The NEC and NFPA have code sections about transfer switches that your electrician should be up on.

The NEC also has a section 625 about EVSEs and what is required when an EV is used as a power source that should be considered even though your system is not interactive.

Sub-section 625.48 is aimed at interactive systems for that use an EV as a power source, but the provisions are a best practices for manual transfer as well, so when you have your set-up inspected there are no snags.


625.48 Interactive Systems. EVSE that incorporates a power export function and that is part of an interactive system that serves as an optional standby system, an electric power production source, or a bidirectional power feed shall be listed and marked as suitable for that purpose. When used as an optional standby system, the requirements of Article 702 shall apply; when used as an electric power production source, the requirements of Article 705 shall apply. EVPE that consists of a receptacle outlet only shall be in accordance with 625.60.

702 deals with OPTIONAL STANDBY SYSTEMS installed to provide an alternate source of electric power to serve loads that, when stopped during any power outage, could cause discomfort etc., intended to supply on-site generated power to selected loads either automatically or manually.

705 deals with connecting additional power production sources to the existing premises wiring system that operate in parallel with the primary source of electricity. This can include utility interactive PV systems, wind systems, fuel cells, energy storage systems, DC microgrids and the like.

Section 705.12 covers load side connections and allows interconnecting an alternate power source to the load side of the service disconnecting means of the other source at any distribution equipment on the premises.

The rules that follow in 705.12(B) provide for every type of possible interconnection scenario that is likely to be encountered. This includes source interconnections made to feeders, taps, and busbars. These rules can be difficult to follow without illustrations and a careful read.

Where distribution equipment or feeders are fed simultaneously (at the same time) by a primary source of electricity (such as the electric utility) and one or more other power sources and are capable of supplying multiple branch circuits or feeders, or both, the interconnecting equipment must comply with 705.12(A) through (E). These sections address interconnecting through a circuit breaker, fusible disconnect, feeder taps or busbars, and also provide the rules on marking the presence of all sources, line and load connections and fastening of backfed overcurrent devices.

625.60 deals with the AC Receptacle Outlets Used for EVPE installed in electric vehicles and intended to allow for connection of off-board utilization equipment. We have to assume Ford complied with these standards when they designed the outlets. "off-board utilization equipment" is basically anything that run on electricity provided by the outlets that is off-board the vehicle.

 

[chl]

PS: always a good idea to have all major electrical installs/modifications permitted and inspected and probably most jurisdictions require it.

It a good quality check on the electrician's work.

I had a shed wired by a local company a 20+ years ago.
The electrician wired the neutral to one of the hot terminals in the shed panel so that the 120V outlets had 240V - I found out when a drill I tried to use burnt up in my gloved hand while installing shelves.

The guy also installed the wire staples so vigorously that in one case they broke the insulation and the hot conductor on the 12/2 Romex - I found that 19 years later when an outlet stopped working because the hot terminal was dead. I traced the fault back to a wire staple that caused an intermittent connection and periodic shorts that opened the breaker! Could have been a fire, got lucky.

Apparently they didn't pull the needed permit or have the required inspection either, which I found out when an inspector was called by a neighbor who didn't like the view of my shed from her backyard. The shed was legal except that the inspector searched for an electrical permit and inspection and found none. The company couldn't prove they had pulled a permit either.

So almost 20 years later I had to get a permit and an inspection.
Could happen when the house is up for sale if a potential buyer does due diligence.

Words to the wise based on my experience.

 

[Maquis]

From what I gather, most modern transfer switches will switch the neutrals as is needed to prevent the Ford GFCI from detecting a ground fault and opening, but good to have the electrician double-check.

The NEC and NFPA have code sections about transfer switches that your electrician should be up on.

The NEC also has a section 625 about EVSEs and what is required when an EV is used as a power source that should be considered even though your system is not interactive.

Sub-section 625.48 is aimed at interactive systems for that use an EV as a power source, but the provisions are a best practices for manual transfer as well, so when you have your set-up inspected there are no snags.


625.48 Interactive Systems. EVSE that incorporates a power export function and that is part of an interactive system that serves as an optional standby system, an electric power production source, or a bidirectional power feed shall be listed and marked as suitable for that purpose. When used as an optional standby system, the requirements of Article 702 shall apply; when used as an electric power production source, the requirements of Article 705 shall apply. EVPE that consists of a receptacle outlet only shall be in accordance with 625.60.

702 deals with OPTIONAL STANDBY SYSTEMS installed to provide an alternate source of electric power to serve loads that, when stopped during any power outage, could cause discomfort etc., intended to supply on-site generated power to selected loads either automatically or manually.

705 deals with connecting additional power production sources to the existing premises wiring system that operate in parallel with the primary source of electricity. This can include utility interactive PV systems, wind systems, fuel cells, energy storage systems, DC microgrids and the like.

Section 705.12 covers load side connections and allows interconnecting an alternate power source to the load side of the service disconnecting means of the other source at any distribution equipment on the premises.

The rules that follow in 705.12(B) provide for every type of possible interconnection scenario that is likely to be encountered. This includes source interconnections made to feeders, taps, and busbars. These rules can be difficult to follow without illustrations and a careful read.

Where distribution equipment or feeders are fed simultaneously (at the same time) by a primary source of electricity (such as the electric utility) and one or more other power sources and are capable of supplying multiple branch circuits or feeders, or both, the interconnecting equipment must comply with 705.12(A) through (E). These sections address interconnecting through a circuit breaker, fusible disconnect, feeder taps or busbars, and also provide the rules on marking the presence of all sources, line and load connections and fastening of backfed overcurrent devices.

625.60 deals with the AC Receptacle Outlets Used for EVPE installed in electric vehicles and intended to allow for connection of off-board utilization equipment. We have to assume Ford complied with these standards when they designed the outlets. "off-board utilization equipment" is basically anything that run on electricity provided by the outlets that is off-board the vehicle.

Since the OP is in Canada, the NEC doesn’t apply.

For the US:
The only parts of that which apply to this thread are articles 702 and 625.60.

625.60 describes requirements of the source, which is integral with the truck. Like you said, compliance here falls on Ford.

 

[Calvin H-C]

From what I gather, most modern transfer switches will switch the neutrals as is needed to prevent the Ford GFCI from detecting a ground fault and opening, but good to have the electrician double-check.

Many now do switch the neutral, but they all don't, so always have it checked.

Looking at the specs for the OP's panel, it appears to switch the neutral.

 

[chl]

Many now do switch the neutral, but they all don't, so always have it checked.

Looking at the specs for the OP's panel, it appears to switch the neutral.

Yes, always verify...even though I have not seen any NEW manual transfer switches that don't switch the neutrals, one can never be too careful.

My old one doesn't - used it with a 8000W running (10kW peak) power gasoline generator a few critical times over the last 15 years - winter ice storm power outage for example.

I will have to do a bit of upgrading when I get a Lightning.

I'd want a higher current L2 EVSE - my current one bought in 2011 was for the Leaf and onlyrequired 30A on a 40A breaker with #8 AWG wire.

For house back-up power via the Lightning 240V 30A outlet, I'd need a new transfer switch that will switch neutrals, and I'll have to add a generator input receptacle near my driveway - currently I have one in the back yard where it was convenient for the gas generator.

These will both require a 50ft run of wire which costs a lot more now than it used to so it actually may be more cost effective to install the back-up via the Ford Charge Station Pro or equivalent.

The generator provided about 240V 33A to the transfer switch, which was good enough to run refrig, microwave, forced air furnace, telephone, TV and Internet node, and lights.

Will the 7200W out of the Lightning be adequate I wonder.
I also wonder if the Ford outlet meets the NEC for a power exporter (625.60, .48, etc.)?
Lights are considered continuous loads, so the code would say I should derate to 24A (80% of the 30A), will this be adequate I wonder - have to do the calculations again...

 

[v2h8484]

I also wonder if the Ford outlet meets the NEC for a power exporter (625.60, .48, etc.)?

Are you sure this applies to the L14-30 Pro Power Onboard outlet and not the J1772/CCS charging port? If it does apply to the L14-30 outlet then IMHO it's code mafia non-sense because it only applies to EV's. That means the same L14-30 outlet on the F150 (non-plugin) Hybrid does not need to comply while the same outlet on the F150 Lightning does. Also, why would this be necessary when no similar code exists for portable generators with the same L14-30 outlet that have been around for decades?

 

[Maquis]

Are you sure this applies to the L14-30 Pro Power Onboard outlet and not the J1772/CCS charging port? If it does apply to the L14-30 outlet then IMHO it's code mafia non-sense because it only applies to EV's. That means the same L14-30 outlet on the F150 (non-plugin) Hybrid does not need to comply while the same outlet on the F150 Lightning does. Also, why would this be necessary when no similar code exists for portable generators with the same L14-30 outlet that have been around for decades?

Yes, this section is about the supply from the vehicle. And the way it’s written, it only applies to EVs. Makes no sense. The NEC is way behind the curve on some of this stuff.

 

[v2h8484]

The NEC is way behind the curve on some of this stuff.

That's a nice way of putting it. Ever since I learned that NEC codes are not developed based on real world data for safety incidents but rather just what some people on the standards committee (with undisclosed external influences/connections) think is a good idea, I can clearly see vendor influences behind some of the codes. I no longer view NEC codes as pure driven by actual safety issues.

 

[Maquis]

That's a nice way of putting it. Ever since I learned that NEC codes are not developed based on real world data for safety incidents but rather just what some people on the standards committee (with undisclosed external influences/connections) think is a good idea, I can clearly see vendor influences behind some of the codes. I no longer view NEC codes as pure driven by actual safety issues.

The code panel is over represented by device and equipment manufacturers who get crap put in the code so they can sell more expensive stuff.
I actually know a guy on the panel. There are a few well-intentioned individuals trying to do the right thing, but not enough of them.

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