Converter Questions!

[Tigerbelle]

I recently noticed a loud humming coming from the outside vent behind the frig in my 17B. Took it in for diagnosis, was told that the battery converter was going out and had it replaced. Brought it home, still hearing a humming noise, although not as loud. Honestly can't remember if it was ever totally quiet, should it be? Also am now confused about how converter works. If I'm on shore power but battery is disconnected, my frig doesn't work at all--not on propane, not on shore, and obviously not on battery. Why is that? Nor do lights or fan, which makes sense. I have solar. Is battery being charged by solar even when disconnected? I'm so confused!!

[gbaglo]

The controls in your fridge are powered by 12V from the battery.
Why would battery be disconnected?

[float5]

Your battery should be on unless you are in storage or maybe need it off for some work being done. Do you mean that you have the master switch for the battery off? Need to keep it on including when plugged in or towing.

You need it to be on when using propane for the refrigerator to get it started.

Yes, you are being charged by solar even if you turn the switch off but usually no reason to turn it off when using the trailer.

[Brian B-P]

Originally Posted by Tigerbelle

If I'm on shore power but battery is disconnected, my frig doesn't work at all--not on propane, not on shore, and obviously not on battery. Why is that? Nor do lights or fan, which makes sense.

I'm guessing that by "battery is disconnected", you mean by the disconnect switch. That would mean that the battery would not charge, but the converter is presumably connected directly to the DC power distribution (fuse) panel, so power should still be available to all circuits (including the refrigerator, lights, and fan). Unless this trailer's disconnect switch is wired unusually, the battery is on one side of the switch, and the converter and fuse panel together are on the other.

It's not clear to me that the converter is working: if the shore power is on, it should be providing power in place of the battery.

Originally Posted by Tigerbelle

I have solar. Is battery being charged by solar even when disconnected?

Normally, yes. The output of the solar charger is usually connected directly to the battery, not going through the disconnect switch.

[cpaharley2008]

Keep that receipt, I have a feeling your old converter was fine but with the switch "off" it was operating 100% time, thus causing a hum from the cooling can.

[Tigerbelle]

Up until the loud humming started I had the battery on all the time. (Meaning, the disconnect switch was in the "on" position.) What I don't understand is why, when the disconnect switch is in the "off" position, despite being hooked to shore power, I have no lights or fan, and the frig, despite being set to AC mode, doesn't work. Is that normal? Because I hadn't ever had cause to turn the disconnect switch to off before, I didn't realize that even with shore power I'd not have lights or fan or frig. And, the fan/hum noise coming from the vents directly behind the frig on the outside of the trailer is still loud and I don't know if that's normal. I am perplexed!

[War Eagle]

Not sure about Escape's wiring, but in many camper brands, 12V DC features continue to run off the battery(ies) even when the camper is plugged into 120V AC shore power. The 120V shore power just keeps the battery(ies) charged so they can keep doing their usual thing (as if boon docking). So if you flip a switch that disrupts the flow of on-board 12V power, no power gets to the 12V features regardless of being plugged into shore power. At least that's true for our current EggCamper.

[Brian B-P]

Originally Posted by War Eagle

Not sure about Escape's wiring, but in many camper brands, 12V DC features continue to run off the battery(ies) even when the camper is plugged into 120V AC shore power. The 120V shore power just keeps the battery(ies) charged so they can keep doing their usual thing (as if boon docking). So if you flip a switch that disrupts the flow of on-board 12V power, no power gets to the 12V features regardless of being plugged into shore power. At least that's true for our current EggCamper.

Yes, in an Escape the battery is still connected to the 12-volt circuits even when the shore power is available and the converter is on (and the disconnect switch is in the normal position). That means that both the battery and the converter are available to supply power - the battery could be charging, or doing nothing, but will only provide power if the converter fails to work. If you disconnect the battery in this case, the converter keeps supplying power; turning off a switch will only stop power to the 12-volt circuits if the switch is between the converter and the 12-volt fuse panel... which seems unlikely, given that the converter and fuse panel are mounted together in one box (along with the 120V AC circuit breakers).

[float5]

Originally Posted by Tigerbelle

Up until the loud humming started I had the battery on all the time. (Meaning, the disconnect switch was in the "on" position.) What I don't understand is why, when the disconnect switch is in the "off" position, despite being hooked to shore power, I have no lights or fan, and the frig, despite being set to AC mode, doesn't work. Is that normal? Because I hadn't ever had cause to turn the disconnect switch to off before, I didn't realize that even with shore power I'd not have lights or fan or frig. And, the fan/hum noise coming from the vents directly behind the frig on the outside of the trailer is still loud and I don't know if that's normal. I am perplexed!

If you turn off the master switch, you have cut the power to everything but solar. That is what the switch is for --- so when in storage you do not drain the batteries. Has to be on to have those things working including when on shore power.

[Kountrykamper]

The converter should be supplying 12 volt to everything when plugged into 120 volt regardless of the battery disconnect switch position providing the breaker for the converter is turned on.

[float5]

Tigerbelle, it certainly can become confusing when you have to think about what is running on 12v and what is running on 120v, and whether you are plugged in, and whether you have solar, and whether there is sun for solar, and whether you left something on that should not be on when not plugged in, and whether......!!!

[float5]

Originally Posted by Kountrykamper

The converter should be supplying 12 volt to everything when plugged into 120 volt regardless of the battery disconnect switch position providing the breaker for the converter is turned on.

I think it is mostly a question of why the refrigerator and such 120v items are not working when plugged into a pedestal. Need the switch on for that, right?

That is how I sometimes find that I have turned off the master switch by unknowingly hitting it. I turn on a light and no light.

[rbryan4]

Cathy is correct. In order to power anything in the trailer except the solar charger, the power isolator switch must be in the on position. When you turn the switch off, you are turning off all power. Being connected to a pedestal makes no difference. Pedestal power just means you're running AC power through the converter to supply DC for the trailer, rather than having the DC power come from the battery.

At least, that's how mine is wired. Leave the cutoff switch on unless you are storing the trailer, shore power or not.

[rubicon327]

Originally Posted by Brian B-P

I'm guessing that by "battery is disconnected", you mean by the disconnect switch. That would mean that the battery would not charge, but the converter is presumably connected directly to the DC power distribution (fuse) panel, so power should still be available to all circuits (including the refrigerator, lights, and fan). Unless this trailer's disconnect switch is wired unusually, the battery is on one side of the switch, and the converter and fuse panel together are on the other.

It's not clear to me that the converter is working: if the shore power is on, it should be providing power in place of the battery.

There have been some confusing answers, but this was very well written and correct. I don't have solar, but that shouldn't matter. The converter and battery are wired in parallel. I was plugged in to shore power the other night doing some work and turned the battery switch off. Nothing happens, except battery is now isolated (can't provide power if I were to unplug and can't be charged by the converter while plugged in), but all 12V items in the trailer still receive power directly from the converter. It sounds to me like you have a wiring issue. It sure would be nice if Escape had wiring schematics of their trailers.

[rbryan4]

Yours is clearly wired differently from ours. When I turn the battery cut-off switch to off, I lose all power, whether I'm on shore power or not. So, I only turn it off when I'm storing the trailer. Others have described the exact same thing.

[tdf-texas]

Check your battery disconnect wiring. It should be installed in the positive battery lead between the battery and anything else. Ie, the battery lead from the positive battery terminal goes to one side of the battery disconnect switch and then the other side of the switch goes to the rest of the trailer circuitry.

If it's wired any other way, it's probably not correct.

[rubicon327]

Originally Posted by rbryan4

Yours is clearly wired differently from ours. When I turn the battery cut-off switch to off, I lose all power, whether I'm on shore power or not. So, I only turn it off when I'm storing the trailer. Others have described the exact same thing.

I didn't mean to imply other trailers are not behaving as described, but that Brian's explanation is correct for our trailer. Based on what you are saying the disconnect must be wired in such a way that it kills power completely to the 12V fuse panel (isolates battery AND converter) which seems odd, but clearly not impossible.

[Vermilye]

Originally Posted by tdf-texas

Check your battery disconnect wiring. It should be installed in the positive battery lead between the battery and anything else. Ie, the battery lead from the positive battery terminal goes to one side of the battery disconnect switch and then the other side of the switch goes to the rest of the trailer circuitry.

If it's wired any other way, it's probably not correct.

There is a difference if you have solar. The output of the solar controller is wired to the battery side of the disconnect switch so that it can charge the batteries even with the disconnect switch open.

[tdf-texas]

Let's look at the various scenarios of trailer electrical use.

Case 1: trailer on shore power. Battery disconnect closed. Solar not needed, battery charging from converter
Case 2: trailer on solar power. Battery disconnect closed. Converter not needed, battery charging from solar
Case 3: trailer in storage, battery not charging. Battery disconnect opened. Solar and converter not needed.
Case 4: trailer in storage, solar charging. Battery disconnect closed. Converter not needed.
Case 5: trailer in storage, converter charging. Battery disconnect closed. Solar not needed.

I see no case where solar needs to connected ahead of the battery disconnect switch.

[Tigerbelle]

Thanks to everyone who has responded! She (my trailer) is back in the shop so that my RV guy can determine if the humming is coming from one of the frig fans, wired to the converter versus wired to the frig (since with the frig off, the sound continues.) I feel as though I've learned a ton about how the converter works, and I'm now thoroughly sold on this forum!