Can't turn off DC converter separately? Any ideas?

[tdf-texas]

Originally Posted by dstreight

^ All the 120v appliances in our 15A, namely the microwave, the induction burner, water heater are 120v only (plus all 120v outlets). The refrigerator is 12v only.

Could a leg, going from the outlet side of the transfer switch to the AC input side be utilized instead of the sub-panel since, in my application, either the AC will come from shore power or it will come from the inverter for all 120v appliances & outlets in the trailer?

Besides the safety concerns, with that circuit you are feeding the converter again from the inverter when not on shore power. Inverter goes through transfer switch, transfer switch feeds WFCO panel, WFCO panel feeds converter power.

Now your back where you started with 12v to 120v to 12v. The point of using a subpanel is to separate circuits that you want to power from the inverter from circuits (like AC, converter, hot water heater, etc.) that you don't.

[Vermilye]

Originally Posted by steve dunham

I have used a 30 amp Commercial / Industrial grade 3 way switch as a transfer switch in similar applications. If the switch is wired properly then only one source of power ( Utility or Inverter) would be allowed to feed the the converter panel at any one time .. It is a simple , cheap and easy to install transfer switch

We were camping at a county park in Northern Mn
One of the electrical pedestals needed work so the workman shutdown the power to that loop and started the repair . All of a sudden the workman lets out a yelp along with a couple of choice cuss words . Turns out one of the trailer owners on that loop , not knowing why his power was off , turned on his homemade , jury rigged inverter system. His inverter power was being back fed through his trailers supply cord , into the pedestal and energizing the whole loop .
Luckily no one was hurt

A good idea to save a bit of money, although make sure the switch is break before make (most are). Also, you should use a 2 pole switch so that both the hot & neutral are switched. Most inverters require this.

As an added note - not necessary in dstreight's case since he has a built in transfer switch. If the inverter is larger than 1500 watts, you will still need a sub panel since the inverter output is greater than the branch circuit ratings (assuming they are #14 wire & 15 amps).

[dstreight]

Originally Posted by tdf-texas

Besides the safety concerns, with that circuit you are feeding the converter again from the inverter when not on shore power. Inverter goes through transfer switch, transfer switch feeds WFCO panel, WFCO panel feeds converter power.

Now your back where you started with 12v to 120v to 12v. The point of using a subpanel is to separate circuits that you want to power from the inverter from circuits (like AC, converter, hot water heater, etc.) that you don't.

I want to supply 120v AC to all 120v AC appliances & outlets (via the inverter when boon docking, which is a majority of the time; but still have the option of running shore power to provide 120v AC and 12v DC when/if) in our little 15A. FWIW, no Air Conditioning in our 15A.

So that's where I'm mentally stuck regarding the recommendation of using a sub-panel for segmented 120v AC circuits.

[tdf-texas]

Originally Posted by dstreight

I want to supply 120v AC to all 120v AC appliances & outlets (via the inverter when boon docking, which is a majority of the time; but still have the option of running shore power to provide 120v AC and 12v DC when/if) in our little 15A. FWIW, no Air Conditioning in our 15A.

So that's where I'm mentally stuck regarding the recommendation of using a sub-panel for segmented 120v AC circuits.

So you are telling me: Gas hot water heater, fridge running gas, no AC.

Any of these devices running on the inverter would bring your batteries down in short order. Even if you had a battery bank big enough to run one of these, your solar panels would never be able to keep up with the current drain. And that's only when the sun is shining.

Then the only device that you would not want to power from the inverter would be the converter. Getting the converter off the AC system when on inverter still requires a sub panel.

[dstreight]

^ I have a 6500wh/400Ah LFP battery; been running everything off the system for a year without issue. Even ran the 11,000btu A/C long enough to prove to the buyer that it worked and pushed out cold air .

Our trailer is ALL electric; no propane whatsoever.
12v fridge/freezer (removed the OEM variant)
120v (750w) 6 gallon marine water heater; once water is at 160F it will keep it hot/warm enough for all our uses including showering for 24-hours+
12v water pump
12v lights
12v (1.5a) diesel Espar heater
2) MaxxAir 12v fans
3000w Xantrex sine wave inverter/transfer switch
120v induction "burner". We use this for quick water heat-up and/or quick meal prep only.
120v (750w) marine water heater
120v microwave (came with the Escape)

The battery charger portion of the "converter" is going to be eliminated one way or another: Not compatible with the LFP battery.

The only feature of the converter that I have a modicum of interest in keeping (aside from being able to utilize 120v/30A shore service): Converting 120v AC shore power to 12v DC for the rare occasions we are camping in a traditional RV park and find ourselves under shade canopy and hence limited solar gain. But, if the complexity of keeping/getting shore power to 12v then we'll just use the LFP bank and fogetaboutit.

[John in Santa Cruz]

your 6500WH battery will run that A/C for about 3 hours, then be completely and totally flat. you would need at least 30 hours of direct peak sunlight perpendicular to a 200W solar panel to recharge that amount of power.

a 20 lb propane tank has the energy equivalent of 120,000 watt*hours in it, two of them doubles that to 240,000 watt hours. $8 or 10, and a few minutes at a propane filling station, boom, another 120,000 watt*hours. no, it can't be used for air conditioning, but it sure can be used for heat, hot water, fridge, and cooking.

[dstreight]

Originally Posted by John in Santa Cruz

your 6500WH battery will run that A/C for about 3 hours, then be completely and totally flat. you would need about 30 hours of direct peak sunlight perpendicular to a 200W solar panel to recharge that amount of power.

The A/C has been sold and removed; not needed for how, where & when we camp.

Right now I've got 550w of solar...would like more for the shoulder months but so far it has worked fine for summer months out here in Nevada where we don't have much shade and/or cloud cover...during the summer anyway .

I didn't want the fumes and mess inside the 'lil trailer so that is why we wanted all electric. The diesel Espar sips a tiny amount of fuel (and electricity); talk about fuel density! And its so much quieter than an Atwood, similar. The 12v marine Dometic uses a fraction of electricity compared to a typical RV 3-way/what it came with. And no vents to suck up dirt & dust now...we find ourselves on dusty stretches of gravel, dirt, playa, etc...

Our application is VERY different from a vast majority of RV'rs.

Hope you haven't been terribly impacted by the CZU fires! The smoke up here in the Carson Valley has been terrible for weeks and since the Creek Fire got started its been beyond terrible.

[Hawkeye Ed]

Here’s what I’ve learned since originally posting my concern that I couldn’t turn off the AC to DC converter/charger section of my WFCO power center without turning off power to ALL AC-powered loads. I wanted to be able to turn off the converter/charger and use the generator for other AC loads.

Thanks to those of you whose answers helped; I also contacted the manufacturer and emailed Karl at Escape Trailers.

It turns out that the AC circuit breakers on our power center were mislabeled by ETI. The power to the converter/charger is NOT connected to the MAIN breaker as labeled. It is connected to the 15 amp breaker that also controls power to the fridge. I’ve found no good answer why the converter/charger doesn’t have its own breaker but apparently this is a common practice.

The reason I wanted to be able to turn off the converter/charger independently is that when I try to charge my dual 6-volt trailer batteries the converter/charger in bulk mode draws too many amps for my Honda EU1000i generator to handle so it shuts down from overload. I contacted WFCO and was told there’s no way to prevent the converter/charger from going into bulk mode.

I received several suggestions on how to deal with the overload. One way was to swap out the standard 55 Amp converter/charger for one with a smaller capacity. Another was to replace it with a Progressive Dynamics 4655 with a remote control that does let you bypass the energy-sucking bulk mode: <http://www.bestconverter.com/PD-4655L-MBA-WildKat-55-Amp-Main-Board-Assembly-for-WFCO-8955-or-Parallax-7155-Includes-4600-Remote-_p_677.html#.X1kK4y2z2CM>.

Another suggestion was to use solar panels and the final suggestion (the cheapest) was to fire up the generator for battery charging before the batteries were discharged so far down.

Luckily, I also have a larger Honda EU2000i that will handle the full load without complaining. I was just hoping to use the smaller generator and save a little weight. But as one person has mentioned, the EU2000i will mostly charge at a quieter, lower speed than the EU1000i would so that’s probably worth the tradeoff.

Anyway, out of this all I learned a lot more about battery charging and hope what I learned is helpful to others. And thanks again for your help.

[Vermilye]

You may still be able to use the 1000 watt generator by turning off all the breakers except the main & the 15 amp breaker that has the converter & refrigerator connected to it. Switch the refrigerator manually to gas (propane), and the only thing connected to the power cord will be the converter.

If the batteries are really low, the 55 amp WFCO converter may draw more than the 1000 watt generator can produce. While doing the math looks like there would be no problem (55 amps @ 14.6V = 803 watts) the WFCO converter is not power factor corrected, and will likely draw more current than the wattage indicates. It would be a good idea to try this with a well discharged battery to determine if there is a problem before you head out.

[sklein]

Originally Posted by dstreight

The 12v marine Dometic uses a fraction of electricity compared to a typical RV 3-way/what it came with. And no vents to suck up dirt & dust now...we find ourselves on dusty stretches of gravel, dirt, playa, etc...

What Dometic marine fridge did you install and what did you end up doing for ventilation? I hadn't thought of the external vents as a dust path!

We are finalizing the build on an E17B and also putting in a Dometic marine fridge. Now needing to revisit the best ventilation model...

[John in Santa Cruz]

compressor fridges still need air flow on the 'warm' side, this needs ventilation, unless you want them to heat your interior

[Brian B-P]

Originally Posted by John in Santa Cruz

compressor fridges still need air flow on the 'warm' side, this needs ventilation, unless you want them to heat your interior

Since the heat which is being pumped out of a refrigerator came from the interior in the first place, rejecting the heat to the interior (as is done in home kitchens) isn't a big problem. The net added heat is equal to the electrical consumption of the appliance, or typically 60 watts while it's actively running.

[dstreight]

Originally Posted by sklein

What Dometic marine fridge did you install and what did you end up doing for ventilation? I hadn't thought of the external vents as a dust path!

We are finalizing the build on an E17B and also putting in a Dometic marine fridge. Now needing to revisit the best ventilation model...

Here's the unit we went with: https://www.truckfridge.com/product/...-refrigerator/

Its a Dometic but made for over-the-road trucks (DC only). We wanted a drawer style with the latch since we typically are off-pavement much of the time. We didn't need anything larger but the space could accommodate taller in our 15A but not any deeper. It has a freezer but it will only keep frozen goods cold and isn't designed to take unfrozen goods to frozen. Again, not something we cared about. It has met all of our needs and expectations. The latch has never opened even after being jostled up/down some fairly rough trails.

We also have a 50L and a 65L compressor type fridge/freezer in each of our respective tow rigs; which is another reason we didn't need larger inside our 15A.

Heat output of the unit is a non-factor. I installed two round vents on the entry door side of the cabinet and along with open space on the bed side of the cabinet there is plenty of flow through ventilation. I camped last month with day time highs in the low to mid-90's (low humidity) and couldn't discern any negative heat effect from the output.

Dometic has a whole line of compressor fridge/freezers including drawer styles too.

https://www.defender.com/category.js...6204%7C2276226

HTH.

Dan

[sklein]

I'm thinking we will drop the exterior vents for the same reasons -- dust control. That is the default with ETI for compressor fridges anyways. The Dometic CRX1140S is 4.8 cu ft inverter fridge and is claimed to consume 565 watts / 24 hours at 90F.

I'm assuming there will be someplace to add interior vents to the cabinet (E17B) if necessary...

[Centex]

Originally Posted by sklein

I'm thinking we will drop the exterior vents for the same reasons -- dust control. That is the default with ETI for compressor fridges anyways.

Please pardon if I missed it, but have you had communication with ETI confirming this detail of the ETI compressor-fridge currently offered as an option only on the yet-to-be-delivered 2021 E19?

[sklein]

I have had discussions with ETI. They have installed compressor fridges (on request) prior to the 2021 options. I had previously requested they include the external vents since they indicated they don't normally include them for compressor fridges.

[sklein]

Originally Posted by dstreight

The 12v marine Dometic uses a fraction of electricity compared to a typical RV 3-way/what it came with. And no vents to suck up dirt & dust now...we find ourselves on dusty stretches of gravel, dirt, playa, etc...

Without the lower external vent how hard is it to clean the fridge coils?

[dstreight]

The way I have our fridge/freezer mounted, I can either pull the custom drawer I made out from above the fridge unit to easily access the coil. Or I can zip out 6 mounting screws and pull the fridge unit out to access any part of it I might need to.

[sklein]

Thanks!