Installed Transfer Switch in House

[BLoflin]

Are there any downsides, either due to code or safety risk, using the interlock method and removing the ground from the truck side cable ? It seems more people have been doing the interlock method versus the transfer switch method in this thread.

This is a continuing point of confusion. You can google it and read for hours.

However, the facts are per NEC (National Electric Code) Bonded Neutral Generators used to power home circuits MUST switch Neutral (as well as Hot) at the transfer switch. Further using a connection (cable/plugs) that removes Ground is also against code.

The code is meant to ensure proper and safe operation under all (or a least most) fail scenarios.

Make no mistake, using a cable with the Gnd clipped open with ProPower to your transfer switch that only switches Hot will work. However, it is not to code, and therefore not "safe" for potential fail scenarios.

Some fail scenarios are safety related (i.e. chance for spark/fire or getting shocked) some are related to potential harmful voltage spikes that can damage connected appliances/equipment.

Some are very rare (lightning striking near generator) some or more possible (spilling liquid onto a power strip on the counter). Some are in between (older light switch that has tens of thousands of switch cycles shorting out).

Some people will claim the truck as a generator is itself insulated as on rubber tires (google lightning strikes car for some videos disproving this).

If it was me, I'd installed the proper transfer switch and do it per code.

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[UGADawg96]

This is a continuing point of confusion. You can google it and read for hours.

However, the facts are per NEC (National Electric Code) Bonded Neutral Generators used to power home circuits MUST switch Neutral (as well as Hot) at the transfer switch. Further using a connection (cable/plugs) that removes Ground is also against code.

The code is meant to ensure proper and safe operation under all (or a least most) fail scenarios.

Make no mistake, using a cable with the Gnd clipped open with ProPower to your transfer switch that only switches Hot will work. However, it is not to code, and therefore not "safe" for potential fail scenarios.

Some fail scenarios are safety related (i.e. chance for spark/fire or getting shocked) some are related to potential harmful voltage spikes that can damage connected appliances/equipment.

Some are very rare (lightning striking near generator) some or more possible (spilling liquid onto a power strip on the counter). Some are in between (older light switch that has tens of thousands of switch cycles shorting out).

Some people will claim the truck as a generator is itself insulated as on rubber tires (google lightning strikes car for some videos disproving this).

If it was me, I'd installed the proper transfer switch and do it per code.

So you're saying using an interlock is ok only with a portable generator. So for PowerBoost usage, can't use the interlock and have to use a transfer switch ?

 

[xtraman122]

So you're saying using an interlock is ok only with a portable generator. So for PowerBoost usage, can't use the interlock and have to use a transfer switch ?

It all depends if the generator has its neutral and ground bonded, that's the big distinction that needs to be made, and why the PowerBoost presents an issue at all. If any generator has the neutral and ground bonded on the connection that powers you interlock, you have the same issue: you have your neutrals bonded to ground in two different places, which is problematic, especially for GFCI.

Many portable generators, while they have the neutrals bonded on their regular 15/20A NEMA outlets, will not have the ones bonded that go into the L14-30R that most people will use on their interlock connection, so it doesn't pose the same issue. On the truck, all outlets are indeed bonded in the same manner (They have to be to remain compliant for just about any other use case per OSHA, for example someone running construction equipment off the outlet in the bed of the truck).

 

[BLoflin]

So you're saying using an interlock is ok only with a portable generator. So for PowerBoost usage, can't use the interlock and have to use a transfer switch ?

Correct, if by interlock you mean the cheap/simple mechanical slide switch that ensure the mains breaker flips off when you flip on the generator connection breaker. This action does NOT switch Neutrals. Of course it needs to be a portable generator that is Unbonded (Neutral to Gnd) to use just the cheap interlock switch.

A regular transfer switch, basically has (or does) that interlock function inside it, but also has space for the dedicated circuits you want to be powered. This also will NOT work with bonded neutral (ProPower).

However the transfer switch you will need for bonded neutral (ProPower) is a transfer switch that "transfers" not only the hots (from utility mains to generator mains) but also Neutral from Mains Breaker Box to Transfer Box Neutral. I.E. It severs the connection from the Main Circuit Panel of all three connections, HotA, HotB and Neutral and switches them to the Generator Connection. And to do it correctly (and safely), it should break the Hots first, follow by breaking the Neutral, then connecting (to the generator connection) the Neutral first, then finally the 2 Hots. So it is really a 4 distinct step process.

 

[UGADawg96]

Correct, if by interlock you mean the cheap/simple mechanical slide switch that ensure the mains breaker flips off when you flip on the generator connection breaker. This action does NOT switch Neutrals. Of course it needs to be a portable generator that is Unbonded (Neutral to Gnd) to use just the cheap interlock switch.

A regular transfer switch, basically has (or does) that interlock function inside it, but also has space for the dedicated circuits you want to be powered. This also will NOT work with bonded neutral (ProPower).

However the transfer switch you will need for bonded neutral (ProPower) is a transfer switch that "transfers" not only the hots (from utility mains to generator mains) but also Neutral from Mains Breaker Box to Transfer Box Neutral. I.E. It severs the connection from the Main Circuit Panel of all three connections, HotA, HotB and Neutral and switches them to the Generator Connection. And to do it correctly (and safely), it should break the Hots first, follow by breaking the Neutral, then connecting (to the generator connection) the Neutral first, then finally the 2 Hots. So it is really a 4 distinct step process.

yeah, I was leaning towards the "cheap/simple mechanical slide switch".

This product linked below was shown earlier in this thread is the only one I've found available online for sale. It looks like it would work, but is more expensive and more complicated to install than the cheap interlock slide switch.

https://www.lowes.com/pd/Generac-HomeLink-Upgradeable-30-Amp-Manual-Transfer-Switch/999908117
"Works with generators equipped with GFCI outlets (no switch neutral accessory kit required)" https://www.electricgeneratorsdirect.com/Generac-6852/p17598.html
"Can be used w/ GFCI and Non-GFCI portable generators"

I do not see any of the reliance X series available for purchase.

 

[BLoflin]

yeah, I was leaning towards the "cheap/simple mechanical slide switch".

This product linked below was shown earlier in this thread is the only one I've found available online for sale. It looks like it would work, but is more expensive and more complicated to install than the cheap interlock slide switch.

https://www.lowes.com/pd/Generac-HomeLink-Upgradeable-30-Amp-Manual-Transfer-Switch/999908117
"Works with generators equipped with GFCI outlets (no switch neutral accessory kit required)" https://www.electricgeneratorsdirect.com/Generac-6852/p17598.html
"Can be used w/ GFCI and Non-GFCI portable generators"

I do not see any of the reliance X series available for purchase.

I saw a couple, but showing out of stock, check later. Saw one that was in stock, but couldn't tell if the seller was US based. Actually found it on Amazon... but not US Amazon, go figure...

However, your electrician should be able to get it, Reliance has Dealers all over US.

 

[UGADawg96]

I saw a couple, but showing out of stock, check later. Saw one that was in stock, but couldn't tell if the seller was US based. Actually found it on Amazon... but not US Amazon, go figure...

However, your electrician should be able to get it, Reliance has Dealers all over US.

I mentioned the powerboost and bonded neutral generators and all three electricians that quoted the work looked at me like I had three eyeballs.

 

[Hullguy]

Why cheap out on the incorrect transfer equipment and jeopardize your house and family?

 

[jeffcrum]

Why cheap out on the incorrect transfer equipment and jeopardize your house and family?

I don't want to cheap out. I want the flexibility of the cheap option ?

Have not talked to an electrician yet. But, what I would like is to move my main box over and replace it with one that I can cut the hot and neutral wires. Single throw would be great. I'd bond the neutral to ground there making it my main entrance to the house. Then, my 'old' main would become a sub box with no bonding. The interlock could be installed there which I think would make it legal.

When the power goes out, I'd flip the new switch off breaking the bond, use the interlock to not back feed the lines (yes, flipping my new main off covers this, but, this covers the code), flip all breakers in my 'new' sub box off, power up the box with the truck, and flip the breakers I need/want.

Thoughts?

 

[UGADawg96]

Why cheap out on the incorrect transfer equipment and jeopardize your house and family?

It isn't a matter of being cheap. It's a matter of electricians here only install whole house generators or interlock switches, the recommended product isn't commercially available, and we are all here to create a dialogue to increase knowledge for the forum/community. ??

 

[BLoflin]

It isn't a matter of being cheap. It's a matter of electricians here only install whole house generators or interlock switches, the recommended product isn't commercially available, and we are all here to create a dialogue to increase knowledge for the forum/community. ??

Maybe, try not mentioning truck/PowerBoost. Just tell them you will have a 7.5KW (I know it's 7.2 but that's not standard in portable gens), with a 240V/30Amp output and is is Neutral Bonded and you need a interlock/transfer switch that is 3 pole (i.e. switches neutral, also). Don't confuse them with new fangled hybrid truck stuff... see if that keeps their eyes from glazing...

 

[Rahul]

It isn't a matter of being cheap. It's a matter of electricians here only install whole house generators or interlock switches, the recommended product isn't commercially available, and we are all here to create a dialogue to increase knowledge for the forum/community. ??

Thanks to everyone for the posts and discussions. I would have totally been in the dark (no pun intended) and really appreciate this thread. My electrician set up an interlock and is going to test the set up with my PB (hopefully this week) by simulating an outage. He insisted that none of this bonded and floating neutral matters ?.I feel that I have more ammo now. Will post once this is all sorted out. One of the main reasons, I got a PB was to avoid purchasing a portable generator for home backup.

 

[BLoflin]

Thanks to everyone for the posts and discussions. I would have totally been in the dark (no pun intended) and really appreciate this thread. My electrician set up an interlock and is going to test the set up with my PB (hopefully this week) by simulating an outage. He insisted that none of this bonded and floating neutral matters ?.I feel that I have more ammo now. Will post once this is all sorted out. One of the main reasons, I got a PB was to avoid purchasing a portable generator for home backup.

Please do follow-up with us. Your electrician will quickly see that it does matter, PB will shut down with GF if he doesn't isolate neutral (or not connect GND).

 

[Hullguy]

I don't want to cheap out. I want the flexibility of the cheap option ?

Have not talked to an electrician yet. But, what I would like is to move my main box over and replace it with one that I can cut the hot and neutral wires. Single throw would be great. I'd bond the neutral to ground there making it my main entrance to the house. Then, my 'old' main would become a sub box with no bonding. The interlock could be installed there which I think would make it legal.

When the power goes out, I'd flip the new switch off breaking the bond, use the interlock to not back feed the lines (yes, flipping my new main off covers this, but, this covers the code), flip all breakers in my 'new' sub box off, power up the box with the truck, and flip the breakers I need/want.

Thoughts?

The correct transfer switch is switching your houses neutral bonding jumper from your normal electrical services to the trucks neutral bonding jumper. Removing the grounding jumper isolates the neutral from the circuit which can cause the electricity to flow down the ground wire. When you open the refrigerator you could get shocked! Or send 240 volts to 120volt devices!

This is where this forum helps with learning new things. When you have an electrician come over to price this job out provide the stipulation that the transfer switch should be “ http://www.reliancecontrols.com/x-series-panel-link.aspx” or equivalent. Jim

 

[BLoflin]

When you have an electrician come over to price this job out provide the stipulation that the transfer switch should be “ http://www.reliancecontrols.com/x-series-panel-link.aspx” or equivalent. Jim

Have to remove that last quote in the link or it won't resolve.
http://www.reliancecontrols.com/x-series-panel-link.aspx

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