Generator transfer switch as service disconnect question?

[slow]

I am looking to add a minisplit AC, would something like this be be code for the required disconnect at the outside condenser? Side benefit it is would allow running it on a generator for hurricane power outages easily and the generator can be in the back yard behind a fence.

https://www.electricgeneratorsdirect.com/Reliance-Controls-CSR302/p1106.html

 

[Chuckster in NJ]

You can use transfer switch this to run the mini split ONLY during power failures....... You will still need a fused disconnect switch for the condenser.

How are you powering the rest of the house?

 

[slow]

good point on the fuses.

I am aware it would only run the minisplit. In this situation, the rest of the house would not be powered, but it would be a way to cool off one big room in the house on the generator, and the generator could be safely kept in the back of the house near the unit.

Maybe I will just run a generator inlet to the back of the house near the minisplit when I run the power for it, then I could power part of the house as well.

 

[rlitman]

good point on the fuses...

How so? A mini-split does not need a fused disconnect. Just a plain old disconnect.

I actually don't see an issue with using a transfer switch here. Transfer switches are just double throw disconnects (where normal disconnects are single throw). Since there's an off position, and a transfer switch will necessarily be rated for disconnecting the current, I don't see the problem. But perhaps someone else with move code knowledge could chime in and point out my error.

 

[wanderer]

My utility connection was provided as a transfer switch and set up that way by my utility supplier. It’s just to 200 amp breaker‘s with a metal plate across them. They are designed to ensure that they cannot both be put on at the same time.

 

[dcg9381]

Interesting question. To me, I'd say it's non-compliant based on the case that both sides of the transfer are active... Or could become active.

It might be compliant in the case of a manual transfer switch with a generator not present (portable generator). But pretty hard to say...

To me, it becomes "is it idiot proof" - and I don't think so in this case.

 

[slow]

Interesting question. To me, I'd say it's non-compliant based on the case that both sides of the transfer are active... Or could become active.

It might be compliant in the case of a manual transfer switch with a generator not present (portable generator). But pretty hard to say...

To me, it becomes "is it idiot proof" - and I don't think so in this case.

your point of is it idiot proof is a good one, The transfer switch does have a line, off, generator switch, so 3 positions, but sometimes KISS is a good idea to follow.

 

[rlitman]

Interesting question. To me, I'd say it's non-compliant based on the case that both sides of the transfer are active... Or could become active...

You're reading it wrong. Transfer switches are all On-Off-On. There is always (by necessity) a neutral off position. It's NOT an interlock.

If it were On1-On2, then yeah, I'd agree. But that's not how transfer switches work.

 

[wyliesdiesels]

good point on the fuses.

I am aware it would only run the minisplit. In this situation, the rest of the house would not be powered, but it would be a way to cool off one big room in the house on the generator, and the generator could be safely kept in the back of the house near the unit.

Maybe I will just run a generator inlet to the back of the house near the minisplit when I run the power for it, then I could power part of the house as well.

Im not understanding why you want to just power the mini-split. why not wire an inlet to the main panel and have the option to power other stuff in the house especially if you dont need the mini-split?

How so? A mini-split does not need a fused disconnect. Just a plain old disconnect.

I actually don't see an issue with using a transfer switch here. Transfer switches are just double throw disconnects (where normal disconnects are single throw). Since there's an off position, and a transfer switch will necessarily be rated for disconnecting the current, I don't see the problem. But perhaps someone else with move code knowledge could chime in and point out my error.

Not true for some mini-splits and even regular air conditioner condensers. some manufacturers do indeed call for fuses. If the nameplate says fuses are required, then the disconnected needs to be fusible with the right size fuses.

 

[rlitman]

Im not understanding why you want to just power the mini-split. why not wire an inlet to the main panel and have the option to power other stuff in the house especially if you dont need the mini-split?



Not true for some mini-splits and even regular air conditioner condensers. some manufacturers do indeed call for fuses. If the nameplate says fuses are required, then the disconnected needs to be fusible with the right size fuses.

I agree that if the nameplate calls for fuses only, then fuses are required. However, I've not seen anything like that in the last few decades. Hell, HACR breakers are now passe, since that standard was absorbed.

As for why you'd just power the mini-split by itself vs an inlet, yeah, that's a little weird, but if it's your primary heat source, I suppose it makes sense to prevent a catastrophic freeze.

 

[dcg9381]

You're reading it wrong. Transfer switches are all On-Off-On. There is always (by necessity) a neutral off position. It's NOT an interlock.

If it were On1-On2, then yeah, I'd agree. But that's not how transfer switches work.

I stand corrected, I didn't know that there was an "off" position. I'd say that it qualifies as a disconnect (just like a sub-panel with a breaker in reasonable distance).