Why automatic transfer switch?

[howson]

...I don't see a problem even if I leave the switch in the inverter position and connect to shore power. Less efficient, but no danger to anything. I have inverter prep, so the circuit I am powering is separate from the one that would be connected to shore power or a generator. ...

I'm not an electrician (but I do stay at a Holiday Inn Express on occasion), so I'd be cautious about the assumption there's "no danger" with this plan. GD installs a transfer switch (or inverter with an ATS) in all their units. If they could get away without the expense of an extra component (ATS) they'd surely do it.

Again, please ensure what you're contemplating doing (assuming it's OK if you leave the inverter on when plugged into shore power) is not something you'll regret later before installing.

Hopefully the knowledgeable folks will chime in with specifics. TucsonJim ? Scott'n'Wendy ? Jkwilson ? ncitro ?

Below is a generic drawing of how GD typically installs an "inverter prep" (your specific trailer may be different).

[TucsonJim]

Again, please ensure what you're contemplating doing (assuming it's OK if you leave the inverter on when plugged into shore power) is not something you'll regret later before installing.

Hopefully the knowledgeable folks will chime in with specifics. TucsonJim ? Scott'n'Wendy ? Jkwilson ? ncitro ?

If the circuit powered by the inverter is physically isolated from the shore power circuits, there is no reason it's not safe. Shore power will power the converter which will be charging the batteries. The batteries will be powering the isolated circuits via the inverter.

Jim

[howson]

If the circuit powered by the inverter is physically isolated from the shore power circuits, there is no reason it's not safe. Shore power will power the converter which will be charging the batteries. The batteries will be powering the isolated circuits via the inverter.

Jim

But...the OP will be powering the same circuits on that sub-panel via shore power (when available). That leads me to believe there could be the possibility of BOTH 120vAC sources being powered simultaneously to the same sub-panel circuits. Isn't that a no-no? Maybe I'm misinterpreting their post/description?

[ncitro]

I think from what I am reading he should be okay. He is still going to use a transfer switch, it'll just be manual, so the shore power and inverter power should remain isolated. As stated, if you forget to flip it you will be relying on the converter to keep up with the inverter draw which could shorten its life and the batteries lives, but for only the occasional accident when you leave it on you should be fine.

[Scott'n'Wendy]

Ya...it doesn't have to be automatic to be safe.

[steveluannj]

I'm not an electrician (but I do stay at a Holiday Inn Express on occasion), so I'd be cautious about the assumption there's "no danger" with this plan. GD installs a transfer switch (or inverter with an ATS) in all their units. If they could get away without the expense of an extra component (ATS) they'd surely do it.

Again, please ensure what you're contemplating doing (assuming it's OK if you leave the inverter on when plugged into shore power) is not something you'll regret later before installing.

Hopefully the knowledgeable folks will chime in with specifics. TucsonJim ? Scott'n'Wendy ? Jkwilson ? ncitro ?

Below is a generic drawing of how GD typically installs an "inverter prep" (your specific trailer may be different).

Thanks for the schematic. I would assume that the reason for an ATS is to make it impossible to do it wrong, and to make things simple for the user. Running an inverter all the time should not be a safety issue, since the circuits are separate, and only powered from one source. It is worth turning off the inverter side when on shore power so that the inverter is not generating heat, and wearing itself out. I plan to do this, and also to choose an inverter with a remote switch so I can power up those circuits only when needed when not connected to shore. I am used to boondocking with a generator, which I run every 3-4 days to charge the batteries, or to use a hair dryer. This new setup is the luxury option for me. Since I will be leaving the inverter off to save power. it would not provide anything other than convenience to have a manual switch- there would be no A/C when the shore power went away and the ATS flipped to GEN until I went and punched the on button on the remote panel. Since my use case is well served by a manual switch, I will take the increased reliability and lower cost of the simpler solution. I can put the savings into a solar disconnect, which my unit also needs.
My current choice for inverter is the Renology 2KW- I really can't support more than that with the battery I have- the BMS is only good for 200A, and 2KW should run any single appliance I can think of. I have a dual 2K generator solution if I need A/C, but I have needed that maybe once in the last 5 years.

[TucsonJim]

steveluannj

The separate circuitry and manual inverter switch are very similar to what I've done in the past, and it worked very well for me. If you haven't made the inverter purchase yet, I'd suggest that you consider a 3kW inverter vs. a 2kW. In the past, I've had a 2kW and when I was running a fairly high current item like the microwave, it would sound an alarm that it was at the end of it's range. Many 2000 watt inverters struggle to really deliver 2000W. Also, if you ever install another battery in parallel, you'll have 400A of power available.

2000 Watts ÷ 13.3 Volts = 150 Amps (The inverter is the limiting factor)
3000 Watts ÷ 13.3 Volts = 225 Amps (The BMS is the limiting factor - You'll be limited to 2,660 Watts)


I wonder if someone manufactures a 2,500 Watt Inverter?

Jim

Jim

[steveluannj]

steveluannj

The separate circuitry and manual inverter switch are very similar to what I've done in the past, and it worked very well for me. If you haven't made the inverter purchase yet, I'd suggest that you consider a 3kW inverter vs. a 2kW. In the past, I've had a 2kW and when I was running a fairly high current item like the microwave, it would sound an alarm that it was at the end of it's range. Many 2000 watt inverters struggle to really deliver 2000W. Also, if you ever install another battery in parallel, you'll have 400A of power available.

2000 Watts ÷ 13.3 Volts = 150 Amps (The inverter is the limiting factor)
3000 Watts ÷ 13.3 Volts = 225 Amps (The BMS is the limiting factor - You'll be limited to 2,660 Watts)


I wonder if someone manufactures a 2,500 Watt Inverter?

Jim

Jim

What brand was that inverter? I know there is variability in the capacity of inverters with the same published rating.

[TucsonJim]

What brand was that inverter? I know there is variability in the capacity of inverters with the same published rating.

It was a Kisae. Here is a link

https://a.co/d/itk6Gbi

Jim

[Jlawles2]

So if you setup a manual transfer switch properly using a multi pole switch (there is a write up here where someone has done this https://gdrvowners.com/forum/operati...ique-solutions), you can keep the feeds separate even when both are powered. Jim did an excellent job writing up his methods. His installation is for a 50 amp (little more wiring), but can be used as a guide for setting up a 30 amp system.

The rotary switch is designed for multiple inputs to be powered and the outputs to be configured. Note the 2-4, 6-8, 10-12, and 14-16 bridge wiring that needs to be installed so the switch will power the output.

[acoleman43]

Thinking I will go manual- it should be more reliable as well as simpler, and I don't see a problem even if I leave the switch in the inverter position and connect to shore power. Less efficient, but no danger to anything. I have inverter prep, so the circuit I am powering is separate from the one that would be connected to shore power or a generator. Thanks for all of your input. This group is helping me a lot.

In my opinion the ATS is much simpler. Once installed, you don't need to do anything....ever. It does all the work for you

However, the idea of a manual switch is simpler. I think it comes down to personal preference.

[TucsonJim]

TucsonJim We are looking at inverters for our “inverter prep” 2023 337 and the manual states it is only prepped for a 2000w inverter - have you seen higher watt inverters on that prepped orange cable (forgot what it’s called). We would like to install 3000 so we can use the microwave (460 Ah)

Hi there.

One of our members Jomani has put together an exceptional tutorial on how to install a transfer switch and 3000 watt inverter using the orange NM-B (Romex) cable. I'm linking one of his posts below. If you subscribe to his YouTube channel, you'll be able to see step by step instructions on exactly how he accomplished this task. It's the best "how to" video I've seen on this topic.

https://gdrvowners.com/forum/operati...pre-wired-gdrv

Jim