Ok, I am a bit confused. I have successfully connected my solar panels to my Mppt to charge my batteries, but now I want to add an inverter as well. So currently I have a generator / shore power>transfer switch>AC for the Rv. So now if I add a inverter do I need another transfer switch? I didn't think it would be ok to have shore power or generator power on the same 120v lines as an inverter? Is this true? Wouldn't the shore or generator feedback to the inverter and damage it? So would I need two transfer switches to accomplish this? So far I haven't seen a schematic that shows how this would work.
Confused? Battery+solar+Mppt+shore power+ generator+ inverter.
- Thread starter Kzneft
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FilterGuy
Solar Engineering Consultant - EG4 and Consumers
You are correct, You really only want one AC source at a time.
Since you have 'shore power' I assume you are talking about an RV or boat or trailer (Something mobile). If you have not already selected an inverter, you may want to look at inverter/chargers with a built in transfer switch. The output of the current transfer switch would go to the inverter/charger and the output of the inverter-charger would drive all your AC.
Since you have 'shore power' I assume you are talking about an RV or boat or trailer (Something mobile). If you have not already selected an inverter, you may want to look at inverter/chargers with a built in transfer switch. The output of the current transfer switch would go to the inverter/charger and the output of the inverter-charger would drive all your AC.
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FilterGuy
Solar Engineering Consultant - EG4 and Consumers
FilterGuy
Solar Engineering Consultant - EG4 and Consumers
This has the advantage of charging your batteries while on the genset or shore power.
From your picture I am assuming the inverter/charger must have a transfer switch built-in to bypass the gen/shore inputs?
John Frum
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Typically the transfer switch is a discrete unit.
Here is an example.
50 Amp Transfer Switch
The Go Power! 50 Amp Transfer Switch provides automatic power switching between two separate 120/240 volt AC input sources.
gpelectric.com
Sorry bit slow on the uptake.
Yes the inverter/charger has an internal transfer switch as well.
erik.calco
Solar Badger
If you have an all-in-one inverter, you can plug shore power to the AC IN of the inverter. The only catch there is how many amps/watts do your loads need, the rating of your current breakers, and the limit of your inverter. For example, if you are running 4000W of loads, then you won't be able to run all that off a 2400W inverter. That's where wiring can get a little more complicated, but is still do-able.
But, if the inverter is more than enough then it would be easy to hook one up. An all-in-one will balance shore power (utility), PV and batteries, and can even charge your batteries with shore power if you want (optional).
Note that an external transfer switch can still be handy even with an all-in-one doing intelligent transferring. For instance, if you manage to trigger a low voltage cut-off, you'll ideally want to direct shore power the old fashioned route while you charge your batteries. Inverters don't work without batteries, so those cutoffs can be an issue. But, you'll use that transfer switch far less frequently.
But, if the inverter is more than enough then it would be easy to hook one up. An all-in-one will balance shore power (utility), PV and batteries, and can even charge your batteries with shore power if you want (optional).
Note that an external transfer switch can still be handy even with an all-in-one doing intelligent transferring. For instance, if you manage to trigger a low voltage cut-off, you'll ideally want to direct shore power the old fashioned route while you charge your batteries. Inverters don't work without batteries, so those cutoffs can be an issue. But, you'll use that transfer switch far less frequently.
FilterGuy
Solar Engineering Consultant - EG4 and Consumers
Yes. The inverter/chargers will typically (always?) have an automatic transfer switch.
Justin Laureltec
Bay Marine Supply Tech Support Manager
Certainly every one that I'm aware of does... though this is where some people get confused by why they also need an external ATS or manual source selector if they have multiple AC sources, such as a generator and shore power; the internal transfer switch of most inverter/chargers is for switching between AC input and inverted power, but (with a few exceptions) cannot handle more than 1 AC input, thus the need for an external transfer switch as well when there's more than one AC source.
A notable exception is the Victron Quattro, which has dual internal ATSs, so it can handle two different AC inputs... but for the price of the thing, if all you need it for are the dual transfer switches, it makes way more sense to just spend a couple hundred (or less) for a 3rd-party ATS and go with a MultiPlus instead -or indeed any of the other inverter/chargers on the market.
Hmmm I think Magnum had/has a unit with dual transfer switches too maybe...
John Frum
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samlex evo also supports 2 ac inputs https://www.samlexamerica.com/products/ProductsList.aspx?cid=S51
FilterGuy
Solar Engineering Consultant - EG4 and Consumers
If it also has a capacity to start a generator when the battery is getting low, that would be a pretty awsome setup.
John Frum
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It does
