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Home Generator Transfer Switch advice

WarWagon

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Wondering what transfer switch I should get for the home/garage? Total of 4 circuits of what I want to power from a portable* 6500W genset 120/240v. The breaker location is on the other corner of the house from where the generator is going to run at so it will need a long run to the genset hook up plug.

Thinking of something like this at Home Depot and paying them to install it. https://www.electricgeneratorsdirect.com/Reliance-Controls-A306C/p50916.html

I am at 10+ hours of total power outage in 3.5 hour outages this year that I can recall. Monsoon season sheared a power pole in half from 60+ MPH wind alone, two tropical storms hit AZ this year, one transformer fire in cold weather, and equipment damage assumed from vehicle hitting power equipment... Look, I don't live in snow, ice, or hurricane areas so I really have a reason to complain. Yeah, I am getting tired of dragging out extension cords esp. at 5AM. (I left the cords in place during monsoon season this year I used them so often on gen power.)

So my plan is to use a Commercial Cummins Onan 6500W 120/240v Single Phase 1800 RPM genset to power Fridge, freezer (10 amps for both at 110v), TV, microwave, LED lights, and a mini split AC system of 12,000 or 15,000 BTU for one room (15A or 20A breakers). I have a doghouse and stand being built for it to keep the rain out of it.

AC System ballpark amps and would use a 240v system most likely:
http://www.fujitsugeneral.com/us/resources/pdf/support/downloads/halcyon-mini-split-2016-full-line-brochure.pdf

*Portable... Yeah right. Just for hook up purposes it's 'portable'. File photo:

onanlift.jpg

https://www.thetruckstop.us/forum/threads/adding-a-6-5-cummins-commercial-120-240v-genset-to-the-collection.47382/
 

WarWagon

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I was planning on using an existing sub panel for genset powered breakers. Thus the transfer switch is break then make for utility to genset. What an I missing?

The main breaker box is double fed both utility and solar. Solar has to shutdown when utility fails. I can't tickle the solar with the generator or it will hit everything with 4kw of power and let smoke out.

I will have this professionally installed due to the extra complexity and just general liability. Come to think of it this is beyond Home Depo installers. I will have to contact a solar installer to even touch it. And they couldn't answer if solar could be combined with a genset long time ago... My understanding is it can't as the solar inverter expects to be able to put out all the Watts into a load. What I don't use goes into the grid load. I don't have an off-grid capable inverter.
 
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ak diesel driver

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If your sub panel can be turned off at the main panel and then your solar supply turned off as well then you don't need another panel at all assuming you have room in the sub panel for a 220 breaker. Just install a 220 outlet at the sub panel and run a cord you make up to fit both ends.
 

Jaryd

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If your sub panel can be turned off at the main panel and then your solar supply turned off as well then you don't need another panel at all assuming you have room in the sub panel for a 220 breaker. Just install a 220 outlet at the sub panel and run a cord you make up to fit both ends.
This is how I’m going to do mine.

You have to remember to cut the main breaker off when done this way without the automatic switchover ( I don’t remember the real names). Once the main breaker is off the generator will backfeed everything that you want it to. Once you see that the neighbors have power just shut the generator down and cut the main breaker back on.
 

jrsavoie

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Price out a whole house unit in Propane. They aren't as expensive as I thought they would be.

When it's super cold, sometime propane will frost up, But then everything has issues when it's super cold. It didn't used to bother me to go outside and eal with stuff. Not so much anymore. I'd just as soon have an automatic.

Not sure who would come hook me up if for some reason I wasn't able to hook things up myself
 

WarWagon

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Was just figuring on the transfer switch panel shown below replacing this 30A sub panel.
"Keeps the generator power isolated from the utility power at all times"

IMO Setup would look something like this with the Genset tie in outdoor plug being on the other side of the house from this panel.

reliance-controls-transfer-switches-3006hdk-64_1000.jpg


The current setup:

IMG_20181224_111555425.jpg


Sub panel that would be re-worked to power what I want. Of course there is only one breaker in it now that needs to be powered.

IMG_20181224_111608455.jpg


Solar ties in at the bottom breaker. Mains is the top 200A breaker of course. The Solar eliminates a meter transfer switch that they have out now.

IMG_20181224_111637209.jpg


Solar inverter with 1500W power outage option to a single plug. SMA Sunny Boy 4000TL-US

IMG_20181224_111817068.jpg

1500W isn't enough and don't work at O-Dark-thirty. Wasted effort that I pulled teeth and broke arms to get installed inside rather than outside at inverter.

IMG_20181224_121629765.jpg
 
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WarWagon

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Maybe I am overthinking this. I just need a transfer switch box between the sub panel and the main panel.
 

Will L.

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I am kinda too tied up to look closely at this right now with family stuff going on today and tomorrow. But how they tied in the solar - i dont think is up to code because if power is down and your solar is outputting, that could backfeed trough the meter charging the line, go through a transformer and kill a lineman working on the system.


Although I’m a residential electrician, Not an expert here- best is call around local electrical contractors and find one that frequently does generator and solar systems for residential.

Here’s why- and the dilemma your facing:
That is The main problem with not just adding a breaker like AK suggested- if generator is running and you forget to turn off main- death of a lineman.

Backfeeding the generator into the solar should not be any more of a problem than the city electric backfeeding the solar.

Here you have to have a 2 meter system with a one way shunting system to protect the lineman. Local codes like that can change one city to the next but isolated power source for the lineman is national code.
 

WarWagon

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When the utility goes down the Solar Inverter shuts off and stays off until it gets tickled by the utility again. (It's my understanding the inverter actually waits for the lead of the AC sinewave from the utility before it puts power out each and every reversal.) Then after a delay with utility power on it starts back up. This setup was done by a long standing solar contractor that's still around. Then it had to be inspected by SRP, local power co, before it could start up. I have a call out to them to see if they can handle a transfer switch install as they do electrical and solar.

As Solar is a 'current source' it simply can't be cost effectively used without a battery bank load etc. in off-grid mode. Off grid is a different story, but, not the goal here. The inverter takes 600v DC and makes it 220v AC via FM, black magic, etc. - Just don't need to F with 600v DC for short genpower run times. Have enough generator to do what I want so NBD. Fuel consumption between no-load and full-load still doesn't make a big difference.

Maybe a switch like this would work with the existing sub panel. Stepping off the dual fed main panel with the sub panel looks like the easy way to do this.

https://www.homedepot.com/p/GE-100-Amp-240-Volt-Non-Fused-Emergency-Power-Transfer-Switch-TC10323R/100171587

ge-safety-switches-tc10323r-64_1000.jpg

ge-safety-switches-tc10323r-40_1000.jpg
 

WarWagon

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Price out a whole house unit in Propane. They aren't as expensive as I thought they would be.

When it's super cold, sometime propane will frost up, But then everything has issues when it's super cold. It didn't used to bother me to go outside and eal with stuff. Not so much anymore. I'd just as soon have an automatic.

Not sure who would come hook me up if for some reason I wasn't able to hook things up myself
I have given this automatic lot of thought. Let me give it some perspective that may not apply to your location.

As it stands I would need to throw a manual transfer switch, open the fuel tank vent, and hit the start button on the genset: Most likely in the rain. And plug in the generator to home cable. I explain why I would leave it unplugged.

I have 4 gensets to choose from in case one has problems. That's counting the RV that isn't accesable most of the time in storage. (I am working to change that with a additional concrete driveway/pad.) The major cost without power is food loss and medical stuff. Medical I can power off an inverter, in stock, and one of the 5 car batteries ( and 2 genset bats) I have around.

There have been a couple times where starting a genset is simply a bad idea. One is 60 MPH winds blowing the rain sideways. This situation burned out some generators at a local Casino closing them for months while they made repairs. Same storm also damaged my home. Another is the dust storms we get. The sand in the air is known to sand blast the insulation off the generator winding. An Automatic genset would start and fail.

I have to use the gasoline 16 gal, every 6 months. (Yeah, I need to keep a little more fuel onhand so I don't have to siphon things.) So I test run the sets every month and run them awhile to burn off the fuel. Power the 5HP compressor or just a heater.

Now we consider a full auto genset with a 275 Gal propane tank. (No Nat Gas utility in my area.) It costs as much as a used running 6.5 diesel truck. I need 11-22kW for whole home AC otherwise why bother. It's got Wi-Fi and every electronic bell and whistle known to man. If any single one of the dammed bells or whistles don't work the GodForDammed thing Will Not Start. No, you can not bypass the fried board and light it off. Parts take days or longer to get. At some point a Cell Phone Alert that the genset did it's weekly self test becomes irrelevant when we loose sight of the purpose of the emergency generator and wind up with nothing during a said emergency. 3600 RPM screamers unless I go with a used $price$ larger liquid cooled 4 banger 1800 RPM set in the 22KW range.

Costs of a service call can be insane as they play the short labor time longer 'parts only' warranty game. They never fail between 8-5...

Engine failures are rare but happens. Genhead failures do happen, but are also somewhat rare. Electronic Krap going BANG! with or without smoke, well, you can count on it. Lightning strikes blowing a transformer tends to have collateral damage to anything hooked up. This includes the transfer switches going out. Even the "Oh-No aka Onan's" I have are known to pop the $250.00-$450.00 voltage regulator if loaded when you run out of fuel let alone from high slip ring resistance. That 3800W Homelite Genset I have is a dirty power set regulated by a transformer and engine RPM, but, bulletproof vs. the Onans I have. (Older Onans with a transformer regulator are also bulletproof.)

I will trade a little for electric start and quiet 1800 RPM.

Said strike like this is not recoverable by a generator for the building that gets hit. This very storm via a direct strike blew out all the network cables and 120v wireing in a building. Strikes like this can weld breakers "on" and burn the place down. Yes, I am FN NUTS for taking this picture even from a vehicle.


strike 2.jpg
 
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WarWagon

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So I am looking at what the Onan 6500W can do and wondering if it should do it...

It's rated at a sky high 14KVA for motor starting. Engine is rated at 14HP at 1800 RPM (and 25 HP at 3600 RPM it won't see.) 27A at 240v. This is why you move it with a cherry picker...

The 3 ton whole house AC has a 16.7 RLA and 79.0 LRA. Min circuit amps 22.1. Max fuse/breaker 35A. Hard start kit just to be sure, but, it looks like the Onan can run the whole house AC with power to spare for the fridge and freezer. (10A total at 120v for those.)
 

ak diesel driver

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Sounds kinda over rated for what it is my 13hp gas generator is rated at 6500w. It probably wouldn't start a 2hp motor even on 220v pretty healthy load starting a 1 1/2 hp motor on my wheelbarrow compressor. Granted you probably have quite a bit more torque. My onan diesel 6000w is under rated as it's been load tested all the way to 8k anymore than that and it belchs black smoke and bogs down. I had a 12k end put on it for motor starting and did succeed in starting a 5hp motor but totally unloaded.
 
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