Add new inverter, or replace Charger to ERA 170M?

[BigFatGuy]

The rig in question is an ERA 170M with a high end Charger, a 2-inlet auto-transfer switch (Gen/Shore Pwr), and no inverter.

The charger is pretty top-of-the-line, so I'd like to avoid replacing it if I can. I figure, it wouldn't be hard to install an inverter and replace the transfer switch with a 3-input one... BUT:

As I understand things, that would create a loop where the inverter generates AC from the batteries that the charger would use to recharge the batteries.

So, is there a way to do it that I'm missing, or should I just replace the charger with an all-in-one unit?

[booster]

Originally Posted by BigFatGuy

The rig in question is an ERA 170M with a high end Charger, a 2-inlet auto-transfer switch (Gen/Shore Pwr), and no inverter.

The charger is pretty top-of-the-line, so I'd like to avoid replacing it if I can. I figure, it wouldn't be hard to install an inverter and replace the transfer switch with a 3-input one... BUT:

As I understand things, that would create a loop where the inverter generates AC from the batteries that the charger would use to recharge the batteries.

So, is there a way to do it that I'm missing, or should I just replace the charger with an all-in-one unit?

What charger does it have in it. Everyone's idea of top of the line is somewhat different, so would be good know.

[BigFatGuy]

Intelipower 9200

[rowiebowie]

Originally Posted by BigFatGuy

Intelipower 9200

I'm not sure what it is you need, but you can call Progressive Dynamics. They should be able to advise you on compatibility with their Intelipower 9200.

Good luck.

[booster]

The PD chargers are good chargers, but do have a bit of an odd profile compared to most others. Having a Charge Wizard pendant on it and a battery monitor to watch charging allows you to control the charging very precisely, but with manual inputs on the pendant. About the best step up would be a Magnum with inverter, monitor, and remote which can do all the accurate charging automatically. They are quite expensive though.


If you do get a standalone for your system, you would need the 3 input auto transfer switch. You also have to make sure that the transfer switch switches all 3 wires as on the inverter you would want to have neutral and ground bonded at the inverter but it has to be unbonded when on shore power or generator.


How big an inverter are you looking at? PSW or modified sine wave? What do you need to run?

[BigFatGuy]

Originally Posted by booster

The PD chargers are good chargers, but do have a bit of an odd profile compared to most others. Having a Charge Wizard pendant on it and a battery monitor to watch charging allows you to control the charging very precisely, but with manual inputs on the pendant.

I have the pendant, but I'm not a fan of manually nursing the charger... I mostly used it to figure out if my solar charger (zampf) was spoofing the charger into going into maintenance mode instead of the full charge... and it appeared that it was, so I installed an on-off switch in the solar system.

Originally Posted by booster

About the best step up would be a Magnum with inverter, monitor, and remote which can do all the accurate charging automatically. They are quite expensive though.

This isn't an emergency repair. I've got time to do it "right". i'll look into Magnum's hardware.

Originally Posted by booster

If you do get a standalone for your system, you would need the 3 input auto transfer switch. You also have to make sure that the transfer switch switches all 3 wires as on the inverter you would want to have neutral and ground bonded at the inverter but it has to be unbonded when on shore power or generator.

I'll keep that in mind. There is a manual ship/shore rotary switch that's 4 positions, 3 poles that i'm thinking about using... I figure, the auto systems may not be doing exactly what I like at any given moment.

Originally Posted by booster

How big an inverter are you looking at? PSW or modified sine wave? What do you need to run?

PSW, just because I like the idea, and I'm not sure exactly what I'll be hooking up in the future.

3000W, because we have a 30A system in our rig, and that's pretty close. also, it's going to be installed in a somewhat warm part of the rig, and I don't want to shave too close with the inverter needed cooling.

Right now, it's mostly my microwave/convection-oven, a laptop, a toaster. We hardly use the A/C, so that's not an issue. Depending on how we attack some other issues, there might also be a digital projector, media server...

[booster]

Have you increased you battery capacity to be able to handle all that use?


I think your model came with a couple of gp31 AGMs so would be around 200 amp hours, unless there were other options.

[markopolo]

Edit: I was typing when Booster posted so sorry for the duplication re: capacity.

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How many batteries or what is the total battery capacity in your ERA 170M?

If 200Ah for example, then give up on the idea of running the air conditioner.

I do like whole house inverter setups for the convenience & went that route in a Class A that I had. An alternate method would be to allow powering of only a single circuit through an inverter thus avoiding the circuit that the charger is currently on. If lucky, that single circuit will have outlets where you need them. That's how it's done in my van.

Look at your microwave oven plug to see if is 15A or 20A & also to see if there's an alternate outlet nearby. In my van, the microwave oven is on a dedicated circuit but there's an outlet that is on the inverter circuit close by so I can alternately plug it there.

[BigFatGuy]

Originally Posted by booster

Have you increased you battery capacity to be able to handle all that use?
.

Not yet, but lithium is on the horizon.

[BigFatGuy]

Originally Posted by markopolo

Look at your microwave oven plug to see if is 15A or 20A & also to see if there's an alternate outlet nearby. In my van, the microwave oven is on a dedicated circuit but there's an outlet that is on the inverter circuit close by so I can alternately plug it there.

Ignore my previous response. i was over-imagining things.

Rigth now, we have no inverter, AND the microwave is kind of off on it's own... plus, I don't like the idea of having to remember to plug it back and forth... although, small-ish inverters are not too expensive, and it might be a useful thing to do in the short term... at least I'd have toast in the mornings.

[booster]

Lots of information on adding an inverter on the forum, but when you say small inverter and toast in the same statement we might have an issue


I think most toaster take at least 1000 watts so you would need to supply more than that. You will probably need at least a 1500 watt inverter for that purpose.



I think most of use would think of small inverters as what would be used to charge laptops, phones, etc. We have two 120 watt ones in our Roadtrek. One to run the audio/video stuff, and one to charge other things. The turn on with switches as needed. We leave the Magnum 2000 watt off unless we need the microwave or maybe a hair dryer. The Magnum does run the entire van if we have it on, but has about 1.4 amps of parasitic loss when idling, so it stays off.

[markopolo]

Lithium, Magnum, rewiring, DC to DC charger, etc. probably $4,000 starting point DIY.

1800W PSW inverter with built in transfer switch (example: http://www.classbforum.com/forums/f6...rice-9936.html ) will power an entire AC circuit in an RV probably $500 DIY. It'll run a Keurig or toaster or toaster oven or TV or non convection microwave oven or charge a phone for example.

[JohnnyFry]

I have a 660 watt toaster and a 600 watt B&D coffeemaker which I use with my 750 Watt TrippLite (not at the same time, of course)

[BigFatGuy]

Originally Posted by markopolo

Lithium, Magnum, rewiring, DC to DC charger, etc. probably $4,000 starting point DIY. .

Exactly why I'm doing it one piece at a time.

[booster]

Originally Posted by markopolo

Lithium, Magnum, rewiring, DC to DC charger, etc. probably $4,000 starting point DIY.

1800W PSW inverter with built in transfer switch (example: http://www.classbforum.com/forums/f6...rice-9936.html ) will power an entire AC circuit in an RV probably $500 DIY. It'll run a Keurig or toaster or toaster oven or TV or non convection microwave oven or charge a phone for example.

At least that much with the lithium batteries, depending on how big a bank you go with. The 1800 watt inverter will run what he wants, including the microwave if wired in to the inverter or whole coach done, but he won't get a lot of run time on high draw stuff if he only has 200ah of AGM batteries. When I tested our 440ah setup on the Dometic microwave,that pulls over 100 amps starting and 80-90 running if the voltage is decent, I found that if I had the low voltage cutoff in the inverter set at over about 11.0 volts, I would bump off the low voltage cutoff if the batteries were much below 50% SOC. Better at 10.5v, but still getting close, so 200ah would need to be pretty full to get much time for high draw items.


I think if the OP does go with a standalone inverter, with built in transfer switch and neutral bonding, he should at a minimum also wire for a larger battery bank in the future, as if you start running toasters, coffee makers, and especially the microwave, 200ah of battery may start to have capacity issues. Keeping an absorption frig would certainly help compared to moving to a compressor version in the future. If prewired with the inverter, adding batteries gets a lot easier down the road. If he does go to lithium, he would also need a new charger and B to B charger or current limiter, but the inverter and wiring wouldn't need to change at that point.


I am not familiar with how an Era is wired so it is hard to tell how much effort it would take to get the whole van on the inverter. In a Roadtrek with the separate circuit for the small inverter as stock, it was a PITA to do properly.

[BigFatGuy]

The 170M has no inverter, and all the 120V stuff is pretty centrally located (in the base of the large driver-side cabinetry), so it SHOULD be fairly easy.

The under-cabinet area is fairly large, but has a lot of heating ducts and whatnot, so it would take careful planning... but my ultimate plan involves a 3rd solar panel (by removing the TV antenna from over the cockpit), replacing the two AGM with Lithium (although they are under-slung on the chassis... so I need to make sure they won't burst into flames like a 787), HOPEFULLY finding space to install two more Lithium batteries under the cabinetry (but that area gets pretty warm... see 787 concerns).

Booster is correct, an 1800W inverter would likely meet my needs, although I'd like enough headspace to run a toaster AND the water heater on electric/mix power if I want to.... a big part of that decision will be the relative size of the devices.

My current charger can (if I remember right) be set for either AGM or Lithium... which is another reason I was thinking it'd be nice to keep it.

I'm also thinking it might be nice, and hopefully space-saving, to use a manual transfer switch, if only because then I'd know exactly what state the system was in at all times... but I can imagine the wife wouldn't be impressed with that.

And, yes, this will, if my estimates are correct, and if I get everything I want, likely end up costing somewhere up near $10K... so I'm certainly no going to do it all right now.