I read another thread about the radio always being on. Which I plan on addressing. But suspect something much bigger. Maybe a wire somehow shorting but not blowing a fuse? I did see in my storage compartment upfront the wire feeding the light. It's going unprotected through a jagged hole in the aluminum. Because the plastic collar that should be going around it was installed upside down around the wire but not in the hole. Appears like whoever did it decided to leave it that way, rather than cutting the wires, flipping it over and popping it into the hole. Can't think of any other obvious reason why I've got this big of a draw on the battery.
How are you measuring: DC ammeter put into the circuit, clamp on ammeter, battery capacity drop over time?
Here are some possibilities:
The radio as you said.
The CO monitor. This draws a surprisingly large current and may be most of what you are seeing.
The larger campers (above 16') have a door jamb defrost circuit on their refrigerator. There is a separate thread that discusses this. I don't have one and obviously have never measured its draw. I would think that it would be on a thermostatic switch so it would not always be on, but when it is on it probably pulls a fair amount of current. Tinkeringtechie can tell you more.
David
[quote source="/post/4957/thread" timestamp="1415641578" author="@david"]The larger campers (above 16') have a door jamb defrost circuit on their refrigerator. There is a separate thread that discusses this. I don't have one and obviously have never measured its draw. I would think that it would be on a thermostatic switch so it would not always be on, but when it is on it probably pulls a fair amount of current. Tinkeringtechie can tell you more.
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My bet is the fridge (assuming you have a full size model). That would account for 0.5 Amps. Unfortunately it's not on a thermostat. Dometic appears to have taken the laziest approach possible. The frame heater is on whenever the fridge is on and the only way to turn it off is to disconnect the frame heater in the back panel. Try turning off the fridge and see if that changes the current at all.
[font size="3"]Generally a loose, periodically shorting wire, will not produce a steady drain. It either shorts and takes a fuse or it just sits there. From the LL pix of the 20' VRV you do have the larger double door fridge. If so TT is correct as several of us have found. The frame heater draws a constant 0.5 amps whenever the fridge is turned on. Plus there is the fridge control board in the order of 0.1 amps. Add to that the draw of the electric gas valve when the fridge is actually cooling on propane and it's not hard to account for your draw. The LP detector, maybe radio, and any other "always on" devices or chargers add in too. Try TT's suggestion and turn off the fridge at it's control panel. That should make a big difference. As TT says, the only fix for the frame heater is to add a switch in the outside lower compartment. Read the thread and holler if you need help. TT will be right over :D.
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Quote from: @charliem" source="/post/4969/thread" timestamp="1415654914[font size="3"]TT will be right over :D.
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Did someone say my name? Oh... false alarm. I never even added a switch to mine. I just disconnected it.
[quote source="/post/4980/thread" timestamp="1415674189" author="@tinkeringtechie"]
[quote source="/post/4969/thread" timestamp="1415654914" author="@charliem"][font size="3"]TT will be right over :D.
[/font][/quote]Did someone say my name? Oh... false alarm. I never even added a switch to mine. I just disconnected it.
[/quote][font size="3"]Yes, but IIRC you were even talking about a relay to sense shore power. Maybe controlled by your future micro board. Anyway, Camp On! [/font]
[quote source="/post/4954/thread" timestamp="1415640319" author="@antares4141"]
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I took the positive lead off the post on the battery, set my trusty harbor freight meter to amps, put the leads on the meter between the terminal and the post. Only thing that brought it to my attention, since I've had it home & unplugged battery's drained twice in like maybe two days. Fridge is off. I'll read the thread on the frame heater and get back with everybody on what I find out. Might be that it's still running (frame heater) even though the fridge is off. Couldn't get my head up in there to see & you can't easily see it In the picture. Little bushing appears to be upside down. There's a collar on one side & and it's designed to push in from the other. I would cut the wires and turn it around but also looks like there's no room for it to slide into the hole. Something I might not have ever noticed had I not taken the picture because it isn't easy to get my head in a position where I would have been able to see that.
As others have said, I doubt seriously that that wire is shorting to the aluminum, And do you even know if that aluminum is grounded. Automobiles stopped using frame grounds dozens of years ago. Take your trusty Harbor Freight meter, set it to a 12V DC range, hook the positive lead to the battery post and the negative to that aluminum sheet and see if you get voltage.
Wrap those wires will electrical tape to make absolutely sure they don't touch the aluminum and look elsewhere for your problem.
How do you know the batteries were drained in 2 days. The interior lights dimmed? 48 hours at .7 volts is 34 amp hours. If the battery were already partially discharged and it was a small Group 24, then that might make sense.
So hook your meter back up on DC amps, and pull each of the DC fuses until it drops. Then look at what devices are served by that fuse. I don't think they are labeled, but you should notice which devices don't work when the offending fuse is pulled. Then investigate those devices.
David
Quote from: @david" source="/post/4993/thread" timestamp="1415723813And do you even know if that aluminum is grounded. Automobiles stopped using frame grounds dozens of years ago.
[font size="3"]David,
The trailer frame and interior aluminum are definitely grounded to the battery negative and shore power safety ground connections. On the 21RBS the connection is via a #8 AWG solid copper wire. Auto frames are also connected, usually via a direct connection from the battery negative to the engine frame. I would agree that most don't use the frame to carry DC current, although an exception is electric tongue jacks.
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[font size="3"]I agree with the general consensus that .7 amps could be a typical draw for your configuration. What is the condition of your battery, is it old, is it an Elcheapo that came with the unit? You should probably perform a load test on the battery to determine its' condition. [/font]
[quote source="/post/4993/thread" timestamp="1415723813" author="@david"]As others have said, I doubt seriously that that wire is shorting to the aluminum,.
David[/quote]Tend to agree it's not shorting against the trailer. Good to know about newer vehicles not grounding to the frame. Didn't know that. Good suggestion about pulling the fuses and checking the draw, I'll try that when I get a chance. It's a new battery as is the trailer. Says marine starting battery 675 cranking amps don't even think it's a deep cycle. Tape would be hard to get where I need it was considering putting silicone around it to dampen vibration and maybe keep it from rubbing against the Side of the hole. I'll check back in with what I find out.
[quote source="/post/5017/thread" timestamp="1415774959" author="@antares4141"]Good to know about newer vehicles not grounding to the frame. Didn't know that.
[/quote][font size="3"]Sometimes a picture is worth a thousand words. A 2013 Toyota Tacoma:
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[font size="3"]BTW I just checked battery load with fridge off, TV booster off, radio off but not disconnected, all other devices and chargers disconnected. Measured 0.090 Amps (90 milliamps) right at the battery. The only things left on should be the propane detector and minimal draw from the fridge control board and maybe a few mills for the radio control. Anything that has a push and hold button, not a hard on/off switch, may have a slight residual draw.
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Did finally pull fuses one at a time and the readings did fluctuate slightly. Probably the cheap meter. When I pull the ramp light fuse and the propane fuse I get the leak down to .2 amps. Ramp light wasn't on when I performed the test with the ramp light fuse in. So not sure what's going on with that. If I pull out every single fuse in the box I still have the .2 amp draw. So I still have some work to do try to get to the bottom of this. If I find out anything new I'll certainly post it.
Quote from: @antares4141" timestamp="1416035956" source="/post/5099/threadDid finally pull fuses one at a time and the readings did fluctuate slightly. Probably the cheap meter. When I pull the ramp light fuse and the propane fuse I get the leak down to .2 amps. Ramp light wasn't on when I performed the test with the ramp light fuse in. So not sure what's going on with that. If I pull out every single fuse in the box I still have the .2 amp draw. So I still have some work to do try to get to the bottom of this. If I find out anything new I'll certainly post it.
[font size="3"]I don't have a VRV so can't check directly, but some thoughts:
From a safety standpoint it would be inadvisable to wire the propane detector through a fuse, especially if the fuse can be blown by something else. The detector is probably wired directly to the 12V source. Mine draws 0.090 Amps which may account for your 0.2 Amp reading on a "cheap" meter.
If the ramp light really is drawing current when off check for corrosion or metal shavings in the light socket.
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I would assume the propane detector either has a dedicated fuse through the box or some kind of inline fuse very close to the battery? I'll let everyone know what I find out with the ramp lights. Seeing as they are exterior lights and sealed I don't think shavings would be a problem like someone mentioned about interior lights.
[quote source="/post/5116/thread" timestamp="1416147779" author="@antares4141"]I would assume the propane detector either has a dedicated fuse through the box or some kind of inline fuse very close to the battery? I'll let everyone know what I find out with the ramp lights. Seeing as they are exterior lights and sealed I don't think shavings would be a problem like someone mentioned about interior lights.
[/quote][font size="3"]Easy to check. Pull all the 12V fuses and see if the detector light is still on. If it is you've found part of your problem.
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I'm interested in the question of idle DC current draw too, because I'm winter storing my trailer with a battery installed to run the lights (if I need them), but without the shore power connected. I unplugged the radio and the LP leak detector fuses (both in the main fuse box) and then checked for DC draw. There is a little (I don't have an accurate meter, so I have no specific numbers). In looking at the converter manual, I think it is the source of the remaining DC current draw. It must use at least a small amount of power all the time. There may be a separate in-line fuse I haven't discovered yet in the wiring between the battery and the converter, but removing that would eliminate being able to use the interior lights. So, I'll just hook up a battery tender and not worry further.
Why don't you install a battery disconnect ? When you go to your RV, you have to switch the battery on, and you have lights. When you leave, open the switch.
I *think* you can manage to keep a trickle charger on the battery through all this, but possibly you'd have to switch between battery on, battery off, battery on charger. So an A/B/C switch (which might be hard to source, but not impossible).
Good idea on the disconnect. I've read about that in other threads too but didn't do it yet. Easy enough to install in my new battery box and will be useful all year.
The thing about the disconnect is, you still lose charge. But that's due to inherents in battery chemistry, not a phantom load.
It's less, and it's unavoidable. So you have to account for it and mitigate it.
[quote source="/post/5136/thread" timestamp="1416184418" author="@sandroad"] I unplugged the radio and the LP leak detector fuses (both in the main fuse box) and then checked for DC draw. There is a little (I don't have an accurate meter, so I have no specific numbers). In looking at the converter manual, I think it is the source of the remaining DC current draw.
[/quote]Mine was drawing about .2 amps with radio, LP leak detector & ramp lights pulled which isn't acceptable for leaving it in storage with the battery hooked up. Like you I pulled all the fuses and still couldn't get rid of the remaining 2 amp draw. (even the two 30amp fuses) Good suggestion it might be the converter. If you can find the wire feeding it you possibly could put a switch somewhere between it and the battery and solve the problem.
Although that might be a terrible idea cause when you do plug it in and have it switched off at the battery no telling what would happen. I'm almost positive my propane detector is fused at the box anyways. I'll have to double check that. I want to move the detector. They put it in a high foot traffic area and I've kicked it accidentally once or twice already. It would be better near the floor underneath the tv on the side of the fridge where there is no foot traffic.