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waterjosh · 10-29-2020, 09:02 PM

So our trailer did not come with an inverter and I am going to install one. I did it with our last trailer but would like to do it a bit more eloquently this time. My thought was that I could tie in at the generator junction box. We have a Onan 5500 and am going to add a remote switch for the inverter and either turn off the converter at the breaker or with a relay. Obviously not going to use the A/C with it either. Is the junction box for the generator a good time in location?

Thanks

coachmanjay · 10-29-2020, 09:32 PM

You want the connecting cables from the batteries to the inverter as short as possible. They usually say 5 ft or less,

jcussen · 10-29-2020, 10:00 PM

Quote:

Originally Posted by waterjosh

So our trailer did not come with an inverter and I am going to install one. I did it with our last trailer but would like to do it a bit more eloquently this time. My thought was that I could tie in at the generator junction box. We have a Onan 5500 and am going to add a remote switch for the inverter and either turn off the converter at the breaker or with a relay. Obviously not going to use the A/C with it either. Is the junction box for the generator a good time in location?

Thanks

If you are buying a straight inverter, why do you need to turn off your converter. Converter just recharges battery and inverter uses the 12 volts to supply 120. Buy a pass through inverter that will supply your loads even with inverter off when on SP or gen.

waterjosh · 10-29-2020, 10:22 PM

Quote:

Originally Posted by jcussen

If you are buying a straight inverter, why do you need to turn off your converter. Converter just recharges battery and inverter uses the 12 volts to supply 120. Buy a pass through inverter that will supply your loads even with inverter off when on SP or gen.

So it doesn't try to recharge itself via the converter while on the inverter

jcussen · 10-29-2020, 10:31 PM

Quote:

Originally Posted by waterjosh

So it doesn't try to recharge itself via the converter while on the inverter

If wired normally, converter is only supplied by shore power or generator and just charges the batteries. Inverter should only be powered by batteries or if on SP or gen, pass the power through the inverter without it using any battery power to select circuits which do not include the converter.

twinboat · 10-30-2020, 05:17 AM

Tapping in to the generator output, without a transfer switch, will damage the generator with power backfeed or damage the inverter when you start the generator.

If you plan on adding a switch then it can work.
You need to switch off the converter breaker. But you may also want to switch off the water heater, air conditioner breaker, and gas/electric fridge breaker. They all are high watt items.

waterjosh · 10-30-2020, 07:30 AM

Quote:

Originally Posted by twinboat

Tapping in to the generator output, without a transfer switch, will damage the generator with power backfeed or damage the inverter when you start the generator.

If you plan on adding a switch then it can work.
You need to switch off the converter breaker. But you may also want to switch off the water heater, air conditioner breaker, and gas/electric fridge breaker. They all are high watt items.

That is one of the things I wanted to know, I wasn't sure about damaging my generator. I just figured I would switch the water heater and ac off, and usually we set the fridge to Gas when we don't have hookups

twinboat · 10-30-2020, 07:43 AM

You can just plug the shore cord into the inverter and switch off all of the breakers you don't want running on it.

The generator/shore power already has a auto transfer switch.

paul65k · 10-30-2020, 07:53 AM

Quote:

Originally Posted by twinboat

Tapping in to the generator output, without a transfer switch, will damage the generator with power backfeed or damage the inverter when you start the generator.

If you plan on adding a switch then it can work.
You need to switch off the converter breaker. But you may also want to switch off the water heater, air conditioner breaker, and gas/electric fridge breaker. They all are high watt items.

This^^

One thing you might want to look into is an inverter/charger some of which have a built-in transfer switch. These are a bit more pricey but when you consider the increased charging capacity and ability to charge AGM and Lithium batteries as well as built-in transfer capabilities the little extra might be worth it when you make your decision

twinboat · 10-30-2020, 08:18 AM

With an inverter/charger, extensive rewiring will be needed to make it a seemless operation.

You can't run the whole RV thru the inverter/chargers internal auto transfer switch, with the exceptions of some high end models. Then you will still need to switch the fridge and water heater to gas.

waterjosh · 10-30-2020, 08:20 AM

Our trailer already has a Progressive converter, I don't know the model number offhand. I may end up sending back the inverter I just got https://smile.amazon.com/Power-TechO...9VP0RG89H4YDN4
if it would be better to get one with a auto transfer built in

Persistent · 10-30-2020, 09:52 AM

Quote:

Originally Posted by waterjosh

Our trailer already has a Progressive converter, I don't know the model number offhand. I may end up sending back the inverter I just got https://smile.amazon.com/Power-TechO...9VP0RG89H4YDN4
if it would be better to get one with a auto transfer built in

Having an auto transfer EMS system is a great idea. It could be simple. It could be a little complicated. Usually they are used with bigger inverters and bigger battery banks.

You could use the 1500 watt inverter as you proposed. Previous posts have pointed out there may be many manual steps to switch over.

I have the 1000 watt version of that inverter. The 1500 watt version is a little more powerful of course. Mine severely taxes a 200 amp hour AGM battery bank when running a hair dryer on low setting. You would need 300 or 400 amp hours of deep draw batteries to use the full capability of the 1500 watt inverter.

Since my inverter is so limited, I installed dedicated 120 volt wiring keeping it separated from shore power wiring. The inverter provides circuit breaker protection. I can easily control what uses the 1000 watt inverter. I use the inverter for a massage vibrator and power bricks for computers. No microwave, hair dryer, or coffee pot.

The 1500 watt is a bit more powerful. It may run a microwave or coffee pot. You could use a second 120 volt sub panel and connect a limited set of existing circuits to the sub panel. Connect the sub panel to a transfer switch. It will switch the sub panel between house 120 volts and the inverter.

I would do the following for myself if I were doing it:
Connect the microwave outlet and one string of wall outlets to the new sub panel.
Add a new 30 amp branch breaker in the old main panel in place of a now disconnected circuit.
Use 10 gauge wire to the transfer switch.
Use 10 gauge wire from transfer switch to new sub panel.
Use 14 gauge wire from transfer switch to the inverter. The inverter will trip at around 12 amps so 14 gauge is OK.
Don't include the converter/charger as one of the inverter sub panel circuits.
Don't include water heater, refrig or other circuits in the inverter sub panel.

This way you are switching only one or two 15 amp circuits, not the whole 30 amp shore power system.

My advice is worth what you pay for it.

I wish you good luck and happy trails ahead.

waterjosh · 10-30-2020, 10:04 AM

Coffee pot is exactly why we wanted to go 1500w. We would use generator for AC or microwave, but can't risk getting blood into our caffeine systems

Brew the pot then shut it off, even with just 2 golf cart batteries it should handle the brewing for us. It worked in our last trailer with the same inverter