Hybrid Inverter???? AC Use and Small Generator

Goodspike · 06-13-2020, 10:46 AM

A recent electrical thread lead to information on something I've sort of been looking for, but didn't know what to call. Apparently it's a hybrid inverter. Basically an inverter that works with your shore connection to supplement it.

My Yamaha generator has something like that in that it uses power from the starting battery to provide additional surge power for a very short period of time (because it's a very small battery). I've been looking for something like that.

The information I saw was for Magnum Hybrid Inverters, but those seem to be overkill for what I'm looking for. They could stand on their own to run an AC, but for vary short period of time (assuming no massive battery system). I'm looking for something smaller and preferably less expensive.

Has anyone seen anything of the sort?

**creativepart** · 06-13-2020, 11:09 AM

I don't know if any of the more inexpenisve smaller inverters have this feature. The Inverter would have to have 110v passthrough/transfer switching at a minimum and a lot of smaller inverters leave off this feature.

Interestingly, it can be done with smart power management systems separate of the inverter.

We have a Magnum 2k watt inverter - with passthru and transfer switch - but it's not a hybrid model. Our Class A has a Precision Circuits Power Control System built in. This system sheds and adds loads based upon the amount of power coming into the RV. But with a network connection to the Magnum inverter - if the inverter is on and if there is sufficient battery power - the system will control the output of the inverter to use inverter power to augment shore or generator power based on the power needed.

This is super helpful when on 30-amp service and trying to run multiple A/Cs or one A/C and a microwave etc.

I would guess that neither of these features (hybrid inverters or PCS systems) are options that have trickled down to Travel Trailers as of yet. Perhaps some larger 5th Wheels, though.

Goodspike · 06-13-2020, 11:11 AM

Thanks, I'll look into smart power management systems too to see how they function.

It seems like it would be something popular with small trailers so you could get by with a smaller generator.

Goodspike · 06-13-2020, 11:45 AM

Not to hijack my own thread--this question is somewhat related. I'm wondering about the power draw of inverters on batteries. Does anyone know roughly what percentage of a single typical RV lead acid battery would be used up running a 1000 watt microwave for a minute? I'm assuming it would be fairly significant, but have no idea.

DavidM · 06-13-2020, 11:55 AM

A 1000 watt inverter draw requires about 100 ramps, but you are only using it for 1/60 of an hour, so 1.67 Ah but double it at least due to the inefficient high draw. But 3-4 Ahs won't affect a decent size battery bank much.

David

Goodspike · 06-13-2020, 12:04 PM

Thank you David!

**creativepart** · 06-13-2020, 12:54 PM

Also keep in mind inverters use power from your battery bank whenever they are on. Not just when powering a 110v appliance. Most inverter spec sheets will include no load power specs. Magnum's lower cost inverters in TT and smaller B's and C's use .8 to 1.5 amps just idling and not powering anything.

Goodspike · 06-14-2020, 10:53 AM

Creativepart, you mentioned some smart power centers would also help, but I wasn't finding anything on my own. Do you have a brand and/or model to suggest?

**creativepart** · 06-14-2020, 10:56 AM

Look for Precision Circuits Inc. The make the PCS system for RVs. I've yet to see one that wasn't an OEM install. And I've not seen one commonly installed on a travel trailer.

Much more common on 50-amp RVs. I have seen them on 50-amp 5th Wheels and have heard the 30' Airstream with 50-amp service can be ordered with one.

Goodspike · 06-14-2020, 11:02 AM

Quote:

Originally Posted by creativepart

Look for Precision Circuits Inc. The make the PCS system for RVs. I've yet to see one that wasn't an OEM install. And I've not seen one commonly installed on a travel trailer..

Thanks. Trailers really get little attention and few additions from what was available in the 60s. Tank meters and half-ass solar prep seems to be it. Oh, and you no longer need to light the water heater or fridge--that's something.

**creativepart** · 06-14-2020, 11:17 AM

We loved our TTs. But lets face it. The market for TTs is divided in two camps.

Those looking for the cheapest travel trailer that will fit their tow vehicle and their family. And, Airstream buyers that don't care about anything other than it is an Airstream.

We searched high and low for the DELUXE, modern, well equipped travel trailer and every once and a while would find something that came sort of close to that description, but not usually.

Our 3-Arctic Fox TTs were great RVs but looked like they were designed by my grandmother. (And, they were designed by the company owner's wife, so that's probably why,)

If we went back to a TT, at this point we'd just go Airstream. I don't believe there are any other "bumper pull" travel trailers that could suffice. And, I realize they are tough to swallow from a "value" for purchase point of view.

Goodspike · 06-14-2020, 11:38 AM

Quote:

Originally Posted by creativepart

We loved our TTs. But lets face it. The market for TTs is divided in two camps.

Those looking for the cheapest travel trailer that will fit their tow vehicle and their family. And, Airstream buyers that don't care about anything other than it is an Airstream.

LOL. And unfortunately largely accurate.

JoeC · 06-21-2020, 07:53 PM

Quote:

Originally Posted by Goodspike

Not to hijack my own thread--this question is somewhat related. I'm wondering about the power draw of inverters on batteries. Does anyone know roughly what percentage of a single typical RV lead acid battery would be used up running a 1000 watt microwave for a minute? I'm assuming it would be fairly significant, but have no idea.

I calculate 87+ amps (90% efficient inverter) from a fully charged lead acid battery, a little less with lithium batteries as the voltage will be a bit higher. Make sure your cables (gauge size) can handle a 100 amp load. Older lead acid batteries may break down under this size load. If you have two 12V batteries in parallel, the load would be about 44 amps each. Now you need to charge them back up which would take twice the amp hours that you took out with the discharge using lead acid and about 5-10% more for lithium batteries.

JoeC · 06-21-2020, 07:58 PM

Quote:

Originally Posted by creativepart

Also keep in mind inverters use power from your battery bank whenever they are on. Not just when powering a 110v appliance. Most inverter spec sheets will include no load power specs. Magnum's lower cost inverters in TT and smaller B's and C's use .8 to 1.5 amps just idling and not powering anything.

Solution: Get an inverter with a power off option and turn it on only when needed, especially if you are pinching your amp hours.