Questions on manual transfer switches.

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Sleken

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I'd like some opinions about handling the following installation. I've been waffling in my ideas.

I have a recently retired customer that was given a very nice portable generator for his retirement. The generator running watts are 9600. It has a NEMA 14-30L receptacle.

The request is for a manual transfer switch. This generator should handle most of the load except for an electric clothes dryer. Water heater is gas, home has a wall mounted gas heater and a fireplace.

The house's breaker panel has no main circuit breaker.

Is a service entrance rated transfer switch with over current protection required here? The generator does have a circuit breaker. Is a load shedding arrangement required?
 
Sleken said:
I'd like some opinions about handling the following installation. I've been waffling in my ideas.

I have a recently retired customer that was given a very nice portable generator for his retirement. The generator running watts are 9600. It has a NEMA 14-30L receptacle.

The request is for a manual transfer switch. This generator should handle most of the load except for an electric clothes dryer. Water heater is gas, home has a wall mounted gas heater and a fireplace.

The house's breaker panel has no main circuit breaker.

Is a service entrance rated transfer switch with over current protection required here? The generator does have a circuit breaker. Is a load shedding arrangement required?
Click to expand...

You may want to look at something like this. Especially if you have a slpit buss panel with no main breaker.

https://www.lowes.com/pd/Reliance-30-Amp-10-Circuit-Transfer-Switch/4712891
 
if the panel has the room I would go with a lugs to main breaker converter and a manual generator lockout breaker... where he can lock out the incoming and do his load shedding, etc... But depends upon panel space as you need both the converter for the lugs and the incoming DP breaker for the generator...

The other way would be a small panel for the appropriate amperage before the panel, to allow the switching and ATS to operate... thus this panel would become the main panel... and you can still keep the old main panel as having no main disconnect...

Of course... if the old panel did not already have the neutral and grounds separated then you need to do that.

But my own assumption is that since there is no main breaker, the main disconnect is elsewhere and this is a four wire sytem into this panel, but not there so not sure..lol.
 
Adamjamma said:
if the panel has the room I would go with a lugs to main breaker converter and a manual generator lockout breaker... where he can lock out the incoming and do his load shedding, etc... But depends upon panel space as you need both the converter for the lugs and the incoming DP breaker for the generator...

The other way would be a small panel for the appropriate amperage before the panel, to allow the switching and ATS to operate... thus this panel would become the main panel... and you can still keep the old main panel as having no main disconnect...

Of course... if the old panel did not already have the neutral and grounds separated then you need to do that.

But my own assumption is that since there is no main breaker, the main disconnect is elsewhere and this is a four wire sytem into this panel, but not there so not sure..lol.
Click to expand...

I meant to reply to this earlier...

There is no main disconnect anywhere. Utility meter direct to the panel (It is an older home).
 
A few things to consider (subject to any local code amendments).

1. Does the Generator have a floating neutral or bonded neutral? (See Note 1)
2. You'll want to have a TS complementary to (1) (unswitched neutral for a float and switched neutral if bonded)
3. You will need to ground the generator if bonded, but can leave it ungrounded on the float.
4. If the generator has a 120 switch, examine this option in the TS design. (See Note 2)

Note 1: You can verify this by running a continuity between ground and neutral. No continuity is a float. Continuity is bonded.

Note 2: The 120 switch parallels the coils, delivering full power to one of the gen's 120 phases. When you hook up the circuits in the TS, consider any loads that might be able to take advantage of this situation, if so inclined. This will take some thought since it is often at odds with load balancing the 120/240 setting, and you'll lose the other phase when switched.

As for the standard Reliance Controls TS (I have two installed), they don't switch the neutral, so a floating gen is best. And they can't accommodate AFCI/GFCI breakers. For circuits that require AFCI and/or GFCI, you can always replace the first receptacle in the run with an AFCI, GFCI, or AFCI/GFCI as the case may be.
 
ptonsparky said:
I’ve used these in the past and they worked well enough. I’m thinking AFCI requirements may have done them in for those of us under the 17.
Click to expand...

That is just a source selection switch, not a breaker. Unless you are modifying the circuit somehow, that wouldn't apply.
 
With a manual transfer switch, like mentioned in the second post, you are manually switching from one source to the other on individual circuits. You don't need to lock out everything else because either you are using the POCO or the generator to feed the circuit. Can't do both simultaneously.
 
Chamuit said:
That is just a source selection switch, not a breaker. Unless you are modifying the circuit somehow, that wouldn't apply.
Click to expand...

Reliance Controls transfers each circuit individually, bypassing the panel breaker and substituting its own breaker. If the panel breaker is an AFCI breaker, that breaker will be bypassed (along with its AFCI protection) when the TS for the selected circuit is toggled. The RC TS uses a single neutral wire for all TS-switched circuits, connected to the SE panel neutral (and back to the TS neutral bar). All circuit returns land on the SE neutral bar. Those sourced from the generator (based on the TS toggle) ride the shared neutral back to the TS panel and back to the generator. There is no way to meter the neutral return from each circuit at the TS (i.e., at the TS breaker for each circuit). If you can't meter the return current for a circuit, you can't use an AFCI breaker in the TS.

Hence, the only option I'm aware of to maintain code compliance on a circuit requiring AFCI that also uses the RC TS is to install an AFCI receptacle on that circuit.
 
JPinVA said:
The RC TS uses a single neutral wire for all TS-switched circuits, connected to the SE panel neutral (and back to the TS neutral bar).
Click to expand...

Correction: There is no TS neutral bar. The neutral connects directly back through the TS to the generator.
 
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