Is that the right way round ?

[Canada Bob]

Just looking into buying a Generac 8000w for the house we just bought, the house is wired with a transfer switch, so no problems there, the thing is.
I haven't run a generator before except a tailgate, so I was looking at the connection procedure to make sure my wife would be able to connect and switch over if I wasn't home. The following is what the Dealer recommends on their website...

1. Connect the generator to the transfer switch using a gen cord.
2. Start the generator outside.
3. Flip the main breakers in the transfer switch from "Line" to "Generator" power.
4. One at a time, turn on the circuits you want to power.

If we start the generator before flipping the main breaker in the transfer switch wouldn't that back feed into the Utilities Line ?
Even if that was just for a few seconds wouldn't that be potentially dangerous ? potentially deadly ?

Bob.

 

[Zeke]

No, the power from the generator will never reach the grid if the transfer switch is installed correctly. With the switch on the grid there is simply no connection whatsoever to the generator. It is isolated.

(I hope I didn't just reply to a bot. Didn't notice the join date and post count. Let me know about that, please.)

 

[Canada Bob]

No, the power from the generator will never reach the grid if the transfer switch is installed correctly. With the switch on the grid there is simply no connection whatsoever to the generator. It is isolated.

(I hope I didn't just reply to a bot. Didn't notice the join date and post count. Let me know about that, please.)

Hi Zeke, Thanks for the above, appreciated, I'm a chippy / a joiner not an electrician so I'm out of my depth on this, but as with any job I do SAFETY {my own and that of others) is always Job One.

I just can't get my head round where the current is going before I flip from Utility to Gen ?

Bob.

 

[dwasifar]

Hi Zeke, Thanks for the above, appreciated, I'm a chippy / a joiner not an electrician so I'm out of my depth on this, but as with any job I do SAFETY {my own and that of others) is always Job One.

I just can't get my head round where the current is going before I flip from Utility to Gen ?

Bob.

Nowhere. Like where the current from a battery goes when there's nothing connected to it.

 

[dave*99]

The generator will be unloaded until you flip the transfer switch to generator and turn on the individual breakers.

 

[dave*99]

Is your generator neutral bonded to it's frame? Usually when powering a main panel in a house, you want the generator to have a separate neutral and ground (frame). That means not bonded.
Some generators have a floating neutral and some are bonded.

 

[Zeke]

Is your generator neutral bonded to it's frame? Usually when powering a main panel in a house, you want the generator to have a separate neutral and ground (frame)
Some generators have a floating neutral and some are bonded.

If it has a bond lug, he can run a bonding wire to his grounding system or rod. Won't affect the switching.

 

[Canada Bob]

THANKS for the explanations, I'm getting the jist of it now, as mentioned I work with "mallets and chisels" I know when I'm out of my depth, so it's appreciated that you guys took the time. As for the grounding, be sure that I'll look into that...

Bob.

 

[wyliesdiesels]

If it has a bond lug, he can run a bonding wire to his grounding system or rod. Won't affect the switching.

Best to run it to the neutral or ground bar in the main.

 

[Zeke]

I thought it would get there anyway. Is tying a separate bonding wire a violation of the continuous wire rule?

 

[beemerphile]

Unless it is a service entrance rated transfer switch (not likely), it should be a four wire connection with no bond between the ground and the neutral.

 

[dave*99]

I thought it would get there anyway. Is tying a separate bonding wire a violation of the continuous wire rule?

There should be only one point where neutral and ground are bonded and that is in the main panel.
They should be separate at the generator. If not, both the neutral and the ground wire in the generator cord are carrying current.

 

[Canada Bob]

I just checked the spec on the generator that I'm thinking of buying, it says it's a Neutral Floating system, is that the way to go ?
Any downside to that ?

Bob.

 

[Canada Bob]

Nowhere. Like where the current from a battery goes when there's nothing connected to it.

Understood, Thanks.

 

[dave*99]

I just checked the spec on the generator that I'm thinking of buying, it says it's a Neutral Floating system, is that the way to go ?
Any downside to that ?

Bob.

That’s perfect.

 

[wyliesdiesels]

I just checked the spec on the generator that I'm thinking of buying, it says it's a Neutral Floating system, is that the way to go ?
Any downside to that ?

Bob.

Is your cord 4-wire? Along with the inlet?

 

[Zeke]

Well, I'm confused. We don't know that the generator spoken of is 120 or 240 but let's say for the purpose of dicussion that it's 240v witha 4-wire plug at both ends, gen and transfer. We know how that gets wired. Then there's this external lug like on my generator. It's outside the case and has nothing to do with a plug. Might be bonded to the ground in the plug, but it's separate lug just the same. So that makes 5 wires coming from wherever the genset sits. 4 in a cord with a proper plug. I can't seen a fifth wire in a cord being able to be used in any way.

What do you do with a wire and that lug?

 

[beemerphile]

Well, I'm confused. We don't know that the generator spoken of is 120 or 240 but let's say for the purpose of dicussion that it's 240v witha 4-wire plug at both ends, gen and transfer. We know how that gets wired. Then there's this external lug like on my generator. It's outside the case and has nothing to do with a plug. Might be bonded to the ground in the plug, but it's separate lug just the same. So that makes 5 wires coming from wherever the genset sits. 4 in a cord with a proper plug. I can't seen a fifth wire in a cord being able to be used in any way.

What do you do with a wire and that lug?

If your 4-wire cord is terminated correctly you can ignore it.

 

[Zeke]

Why is it there? Maybe to bond a frame you might put the generator on?

 

[beemerphile]

If it was a stand-alone energy service, it would need to be earth-grounded and the neutral and ground would have a bonding jumper. The generator would also need to be bonded if the transfer switch was rated and used as service entrance equipment - in other words the bonding of the system neutral to the equipment grounding system would be done inside the transfer switch.

 

[Canada Bob]

Is your cord 4-wire? Along with the inlet?

Hi, good question, the cord I have is 4 pin, as it the transfer box, would I have to make sure I buy a generator with a 4 pin receptacle ?
I note that some generators that I've looked at in the last couple of days have just 3 pin receptacles. The salesman said that's not a problem as they sell an adaptor, a 3 pin to 4 pin wire about 18" long. Would that compromise the wiring on the transfer switch ?

 

[wyliesdiesels]

Hi, good question, the cord I have is 4 pin, as it the transfer box, would I have to make sure I buy a generator with a 4 pin receptacle ?
I note that some generators that I've looked at in the last couple of days have just 3 pin receptacles. The salesman said that's not a problem as they sell an adaptor, a 3 pin to 4 pin wire about 18" long. Would that compromise the wiring on the transfer switch ?

If the generator has a 3-wire receptacle then that means it’s either 120v only or 240v only.

Yes the generator needs a 4-wire receptacle if you want 120/240

The adapter isn’t gonna magically give you the missing leg

 

[beemerphile]

A generator with a 3-pole receptacle is bonded neutral and is not what you need to power a house. Adapters be damned. Most 4 pin to 3 pin adapters that I have seen are NEMA 14-50 to TT-30. In that case the three pins of the TT30 are hot, neutral, and ground. It is for RV-only use. There is a different 4 pin to 3 pin adapter that gets common use on EV chargers. On those, the 3 pins are L1, L2 and ground. EV chargers do not need a neutral. Neither of these is correct for your use. As @wyliesdiesels noted, one gives 120 volts only and the other gives 240 volts only.

 

[ihateminimumwage]

If it's a GP8000 the OP is looking at, it'll be 120/240vac with a 4 wire (NEMA L14-30R).

 

[Canada Bob]

Thanks for the above, I don't need 240v all I need is to run the lights {all LED's} in the house, the modem, my desktop and to charge phones so that folks can still contact me for work purposes, so there's nothing 240v or heavy duty that I need to keep running, just lights and comms.

Bob.

 

[beemerphile]

Thanks for the above, I don't need 240v all I need is to run the lights {all LED's} in the house, the modem, my desktop and to charge phones so that folks can still contact me for work purposes, so there's nothing 240v or heavy duty that I need to keep running, just lights and comms.

Bob.

Even though those are all 120V loads, there is low odds that all will be wired to the same hot line in the panel - unless, of course, you want to rewire the panel to make it so. If you wish to use a generator with a transfer switch to power selected loads in the house, it seems to me that you are trying to avoid the inevitable.

 

[Canada Bob]

If it's a GP8000 the OP is looking at, it'll be 120/240vac with a 4 wire (NEMA L14-30R).

That was the one I had in mind, a buddy has one, but price does play a part in the decision, from what the guy at Dealership said all I need is a 4,000w to 5,000w generator, he said the GP8000 would be overkill for what I need to do. My buddy who had the GP8000 runs his well, a large freezer and other stuff of his generator, it's really just lights and comms that I need.

The Dealer also mentioned that a smaller unit would burn less gas, he also said the only upside of the GP8000 would be no one would be able to run away with it

Bob.

 

[Canada Bob]

Even though those are all 120V loads, there is low odds that all will be wired to the same hot line in the panel - unless, of course, you want to rewire the panel to make it so. If you wish to use a generator with a transfer switch to power selected loads in the house, it seems to me that you are trying to avoid the inevitable.

Thanks for the heads up, appreciated, I'm just trying to figure out what options I have {do I really need much more than 4000w} and how to avoid mismatching generators and cables with the wiring in the transfer box.

Bob.

 

[dave*99]

Post a photo of the transfer box - or a model number. Some are 30A, Some 50A etc. The Generac you are considering will have a 30A receptacle. You could still use that generator with a 50A transfer switch - with the right cable. There will be an inlet plug on your house to connect the generator. Need to match up to that.

 

[wyliesdiesels]

Thanks for the above, I don't need 240v all I need is to run the lights {all LED's} in the house, the modem, my desktop and to charge phones so that folks can still contact me for work purposes, so there's nothing 240v or heavy duty that I need to keep running, just lights and comms.

Bob.

Even though you dont need 240v, as pointed out by beemerphile, the critical circuits in your panel are unlikely to all be on the same phase.

If they arent and you go with a 120v genset, then you either need to jump the lega in the inlet or will need to move all he circuits onto the same phase.

Also, you need to watch out for MWBCs/multi-wire branch circuits. You could overload the neutral with the right size generator...

 

[SuburbanDad]

Hope I'm not hijacking, but I have this one and a transfer switch:

Westinghouse 7500

It says "neutral bonded to frame."

Also claims "transfer switch ready" and I've used it with mine.

Kosher?

Probably a bit big and loud for Bob's needs, but it's a nice machine.

 

[dave*99]

Hope I'm not hijacking, but I have this one and a transfer switch:

Westinghouse 7500

It says "neutral bonded to frame."

Also claims "transfer switch ready" and I've used it with mine.

Kosher?

Probably a bit big and loud for Bob's needs, but it's a nice machine.

Page 14 or your owners manual shows how to disconnect the bond.
In general, generators used stand alone with some items plugged into them get bonded.
When properly connected to a transfer switch they are typically not bonded.

 

[SuburbanDad]

Page 14 or your owners manual shows how to disconnect the bond.
In general, generators used stand alone with some items plugged into them get bonded.
When properly connected to a transfer switch they are typically not bonded.

You know I've actually read most of the manual, but somehow that part is new to me.

So I should do this:

 

[dave*99]

I would. Provided you have a 4 wire connection between house and generator.

 

[SuburbanDad]

I would. Provided you have a 4 wire connection between house and generator.

I do. Reliance 4 pin receptacle in exterior of garage, run cable from generator out in driveway to that receptacle, which is wired to Reliance transfer switch in garage.

If I am following, this will ensure house gfci circuits work correctly, so I'll definitely do it. I don't use the ones from the generator itself.

 

[dave*99]

I do. Reliance 4 pin receptacle in exterior of garage, run cable from generator out in driveway to that receptacle, which is wired to Reliance transfer switch in garage.

If I am following, this will ensure house gfci circuits work correctly, so I'll definitely do it. I don't use the ones from the generator itself.

This has no impact on house GFCI. They work either way.

 

[wyliesdiesels]

you only want the neutral bonded in one place. this would be the main service panel.... GFCIs wont care about any of this...

 

[SuburbanDad]

Well, now I'm confused. That's the reason cited in the manual...

"... Removing the bonded neutral to ensure proper operation of household GFCI circuits."

 

[wyliesdiesels]

Well, now I'm confused. That's the reason cited in the manual...

"... Removing the bonded neutral to ensure proper operation of household GFCI circuits."

the manual is full of BS. if it were correct then the GFCIs in the house wouldnt work because of the neutral to ground bond in the main service panel.

in reality, the GFCIs only care about whats going on on the load side of the GFCI NOT the line side...

 

[dave*99]

Well, now I'm confused. That's the reason cited in the manual...

"... Removing the bonded neutral to ensure proper operation of household GFCI circuits."

Wylies reason is the correct one.