Transfer switch options

[doorfx]

I have a small solar system in my garage. 12 battery bank, 3000w inverter, 2 310w panels. I want to tie Into my garage 60 amp panel. I've looked at manual transfer switches and electronic transfer switches. Of course the manual ones are cheaper. Anyone have any experience or have any suggestions on a simple inexpensive option?

 

[theoldwizard1]

Is your goal to

1. share the output of your panels with what comes off the grid to offset your costs ?
2. are you trying to run the whole garage ?

If #1, you should have bought a grid tie inverter.

If #2, get a generator interlock kit for your breaker box.

 

[tyme2par4]

Get a generator interlock kit. much cheaper than a transfer switch.

 

[doorfx]

Thx , yes it is #2 I want to have the whole garage run off my system. I won't run the 60 gal compressor off the batteries so I still need city power.

 

[theoldwizard1]

Thx , yes it is #2 I want to have the whole garage run off my system. I won't run the 60 gal compressor off the batteries so I still need city power.

Get a generator interlock kit. much cheaper than a transfer switch.

What he said !

Flip the breakers and the garage is powered by ypour solar set up. Flip back and power is coming from the PoCo.

 

[willlgord]

I'm planning to do almost the exact same thing in my garage but I'd like to run a circuit to the house for emergency backup in case of an outage, just lights and refrigerator. I'm betting that this would be against NEC code though. I recently learned that you cannot have two separate circuits powering an out building.

 

[grantw]

I once read about some guy that had time of day pricing from the poco, and maximized savings by doing battery offsets. He would charge on solar and grid during off-peak times, and have an automatic transfer switch to switch the house over to battery during peak hours.

Pretty neat in my opinion. Here is one of the articles

 

[doorfx]

Unfortunately the generator interlock kit is not legal in Canada. It's not CSA approved and it is not sold in Canada. I might have to make a trip to Montana lol.

 

[grantw]

As much as I would like to recommend a grid-tie inverter... They shutdown if the grid goes offline. My opinion: The whole point of having solar is to not rely on the grid as much, and to generate your own power. Why on earth would I want to NOT generate power if the grid is down? I love the battery system idea, and you should have an interlock kit for your panel, so a backfeed condition is not physically possible; CSA approved or not. Don't feed mains power in to your inverter.

Or look in to one of these

The inverter will pass through grid power and charge your batteries. Once grid power is killed, the inverter kicks on and runs until batteries are drained.

all you need with one of these is a breaker and a sub panel with one of these in-line.

 

[mike93lx]

What he said !

Flip the breakers and the garage is powered by ypour solar set up. Flip back and power is coming from the PoCo.

Are breakers durable enough to be used as a switch?

 

[Mongo68]

Xantrex makes some inverters with built in transfer switches but i think they are 30A max. Maybe run 2 and split the load?

 

[reader2580]

The reason a grid tie system shuts down when there is no power is so it doesn't back feed the grid and kill a lineman. It seems silly to me.

Why couldn't some sort of transfer switch be sued to disconnect the feed to the power company if utility power is lost? This is already done with automatic transfer switches for standby generators.

 

[doorfx]

I really won't have much load. 32' of t-8 fluorescent, fan in my radiant tube heater and some power tool use like grinders. I will try to purchase the interlock switch through hd USA

 

[79firebird]

What size wire are you using to me looks like 4 gage i would change it to bigger. the 3000 watt that was in my van used 0 same as my uncles cabin running 2 golf cart batterys. There is a csa approvedgen interlock as i saw one in costco like 3 years ago in alberta.

 

[theoldwizard1]

I really won't have much load. 32' of t-8 fluorescent, fan in my radiant tube heater and some power tool use like grinders. I will try to prefer the interlock switch through hd USA

While it does ot meet any code anywhere and requires operation by someone who is will to accept the NEGATIVE consequences you can set up the same system WITHOUT the interlock.

 

[doorfx]

Could you explain ? Please

 

[doorfx]

What size wire are you using to me looks like 4 gage i would change it to bigger. the 3000 watt that was in my van used 0 same as my uncles cabin running 2 golf cart batterys. There is a csa approvedgen interlock as i saw one in costco like 3 years ago in alberta.

All batt. Connections are 1awg.
I am looking at a generac one at HD. It's a lot more money at close to $200.

 

[TheEquineFencer]

How many individual circuits do you have in your outbuilding? Amp load?

There's a way to wire an 11 pin power relay to operate as a "poor man's ATS"

I'm not sure about being NEC code legal, but it'll work every time. Maybe someone will chime in about code compliance.

I guess you could do something like this for each circuit, depending on code. The relays are about $22 from Grainger, you can get a base to go with them. I use this at work on some Solar light towers on a 20A circuit.

 

[larry4406]

Could you explain ? Please

All the interlock kit does is mechanically prevent the main and the back feed breaker from both being on simultaneously. If you were to turn the main off and then the backfeed breaker on, the system would work. Never have both on at the same time. This requires you to have your wits together and only similarly trained persons to use this. As this is potentially accident prone, the interlock kit makes it idiot proof.

 

[R.Anderson]

The reason a grid tie system shuts down when there is no power is so it doesn't back feed the grid and kill a lineman. It seems silly to me.

Why couldn't some sort of transfer switch be sued to disconnect the feed to the power company if utility power is lost? This is already done with automatic transfer switches for standby generators.

Frying a lineman seems silly to me.

Main reason is cost for the transfer switch batteries and keeping it simple , Solar Edge, SMA and Fronious all do this this with there grid tie inverters. There is a way to have a grid tie inverter still power your house but it involves a battery bank, another inverter, and a transfer switch.



With a transfer switch you have the ability to run your compressor off of the grid and use the inverter to power other circuits at the same time. I would not want to piss around with switching a interlock every time I wanted to use compressed air.

If ya had an Outback inverter you can set it up to feed the panel and when it cannot fill the power demand it kicks a generator on. I am sure there are other inverters out there that do that as well.

 

[wyliesdiesels]

There have been many lineman who were fried because some idiot backfed the grid when the power was off.

 

[doorfx]

There have been many lineman who were fried because some idiot backfed the grid when the power was off.

That is terrible!!!

 

[doorfx]

The other thing I forgot is , code here in Canada states any receptacle has to be on an AFCI breaker. I also have two 30 amp circuits, one is 240v for the compressor and the other is an rv plug.
1 circuit for lights , garage door opener outside light and 5 receptacles.
1 circuit with 3 receptacles and an outside light.
1 circuit with 2 receptacles
1 circuit with an exterior gfci
1 circuit for radiant tube heater
I will be adding one more with a 20 amp breaker and 1 receptacle.

 

[reader2580]

There have been many lineman who were fried because some idiot backfed the grid when the power was off.

This is why grid tied systems shut down if power is lost. What I don't understand is why they can't use a transfer switch to disconnect from the grid when this happens like a standby generator?

It seems silly to have your own power generation system that doesn't work if your power is out.

 

[wyliesdiesels]

This is why grid tied systems shut down if power is lost. What I don't understand is why they can't use a transfer switch to disconnect from the grid when this happens like a standby generator?

It seems silly to have your own power generation system that doesn't work if your power is out.

Agreed.

Ive often wondered that myself.

 

[doorfx]

Exactly^^^^^ that is what I want to do. So I will buck up and get what is required to do it properly.
Is there any issue using one of these with AFCI breakers in my existing panel ?

 

[tyme2par4]

This is why grid tied systems shut down if power is lost. What I don't understand is why they can't use a transfer switch to disconnect from the grid when this happens like a standby generator?

It seems silly to have your own power generation system that doesn't work if your power is out.

Because you would need batteries to easily use the output. The inverter puts out whatever power the panels are producing. If that is more than you are using, it would shut down to to over voltage. If it's less that you are using, it would shut down due to under voltage.
There are hybrid inverters that will switch over, but they require a battery bank to even out the power demand.

 

[doorfx]

Well thanks to a very helpful member on here I am now the proud owner of an emergen 6 circuit transfer switch much like the one posted above. It even has one 240 breaker!! Thanks jayoldschool !

 

[TheEquineFencer]

out of curiosity, how much was it?

 

[doorfx]

Much less than new and it is new.
New ones can run $300 here in Canada.

 

[doorfx]

I contacted the company that makes the transfer switch. They said that because the transfer switch uses mechanical breakers to switch from gen to utility, the breaker can cause an arc when switched, and it's common. The arc is what trips the AFCI I am assuming. They called it a nuisance trip and there is no need for concern.

 

[doorfx]

I received my transfer switch !!!

Now can any one tell me the best way to go from this.

To this.

The cord the transfer switch came with is 10/4.

 

[wyliesdiesels]

The outlet in the last picture is a NEMA TT-30 120v 30a and is only for RVs.

 

[doorfx]

Yes I know, that's why I was asking. I want to go from my 3000 w Honda with that plug to my generator transfer switch with the 4 prong plug. The picture I took was just for reference and is the plug on the out side of my garage that I installed for my rv.

 

[wyliesdiesels]

O i missed the text in between pics.

If u want 120v/240v which is what the 14-30 would provide, u wont be able to use the TT-30 as its 120v only. U will need a 14-30. No way around it.

And thats why it says on the outlet 'RV use only'

 

[doorfx]

Can I not change the cord end on the transfer switch cord (14-30) to the generator style plug and just get 120v ? I don't need 240 as I will run the compressor off utility power. The rest of the garage is 120v and I will run it off solar. I want to use the same style plug/cord.
I often see RVs with a "dog bone" that goes from 50a 120/240 to 30a power. Is something like that possible?
Otherwise this transfer switch I purchased is useless to me.

 

[doorfx]

Anyone?

 

[doorfx]

Will this work ?

http://m.ebay.com/itm/Generator-30A...0A-Female-Pigtail-Adapter-15872-/252423231466

 

[wyliesdiesels]

O ok i thought u wanted 240v and thats why u were bragging about the TS having 240v.

Dont replace the cord end. U can use an adapter but that one pictured would be a suicide cord the way u want to use it because of the male 14-30.

Get a male TT-30 to female 14-30 so that it isnt possible to have any live blades.

 

[doorfx]

Thanks I appreciate the help!!!
Just an FYI... I wasn't bragging , I was pleasantly surprised , so I thought I would share in case anyone else wants to do this.