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Parasitic Battery Drain

WoodcarvingGypsy

WoodcarvingGypsy

Member
I've noticed that there may be a parasitic drain on the batteries when the DC switch is turned off. Has anyone seen anything like this or is there something hooked in before the switch? I don't have the camper setting where it can be plugged in at the moment so I'm a bit concerned that the batteries will drain.

At some point, I will put a second disconnect in the line between the battery and the first buss bar. I'mn also going to put in a Thornwave monitor as well.

Observations and suggestions appreciated.
 
Todd80

Todd80

Well-known member
Yea that happens regardless of RV make. When my camper is in storage for the winter, I like to remove the batteries and put them in my garage where I will hook up the battery charger every 3-4 weeks. Even with the batteries unhooked, they will slowly loose charge over time.
 
WoodcarvingGypsy

WoodcarvingGypsy

Member
So much for the factory disconnect. I checked for apparent DC draw, all lights went off so I suspect it may be the jacks and the propane detector. I'll go tomorrow and disconnect the ground. I had to do a second switch on our previous camper as the factory switch didn't get it done.

Todd80, thanks for your help.
 
Jim Beletti

Jim Beletti

Owner Experience Liaison
Staff member
The propane leak detector is in fact a parasitic load.

It is wired around the cut-off switch per RVIA specification.
 
D

darrell

Well-known member
One note, several people have reported that their disconnect was wired backwards on the power panel and did not disconnect power. Mine was that way. Easy switch, but if I leave the RV for 2 weeks, even with the disconnect engaged, the batteries are dead.
 
D

darrell

Well-known member
Yes, I typically do that. I do have a small portable solar panel I use for maintaining the batteries while parked in storage during the summer months.
 
C

c2m54

New member
WoodcarvingGypsy said:
I've noticed that there may be a parasitic drain on the batteries when the DC switch is turned off. Has anyone seen anything like this or is there something hooked in before the switch? I don't have the camper setting where it can be plugged in at the moment so I'm a bit concerned that the batteries will drain.

At some point, I will put a second disconnect in the line between the battery and the first buss bar. I'mn also going to put in a Thornwave monitor as well.

Observations and suggestions appreciated.
Click to expand...
Yes, I observed the exact same thing. According to the manual the battery disconnect switch will disconnect all DC power to the coach, but the factory is not wiring them that way. I had to rewire mine.
 
D

darrell

Well-known member
One thing to consider for those who are disconnecting their batteries entirely - make sure hook them back up for towing because the break-away switch and brakes will not function without the batteries hooked up. By design, there are several things that will stay powered on, even with the disconnect switch in place and working. Aforementioned brakes, CO and propane detectors, lights, maybe hydraulics for stabilizers, will all work with the disconnect engaged. I believe I read they may be changing that to complete disconnect the batteries from the coach, but I am not sure. In my case, I just had to switch the leads on the power unit inside the trailer coming from the battery / disconnect switch.
 
C

c2m54

New member
darrell said:
One thing to consider for those who are disconnecting their batteries entirely - make sure hook them back up for towing because the break-away switch and brakes will not function without the batteries hooked up. By design, there are several things that will stay powered on, even with the disconnect switch in place and working. Aforementioned brakes, CO and propane detectors, lights, maybe hydraulics for stabilizers, will all work with the disconnect engaged. I believe I read they may be changing that to complete disconnect the batteries from the coach, but I am not sure. In my case, I just had to switch the leads on the power unit inside the trailer coming from the battery / disconnect switch.
Click to expand...
I agree. For me it was a simple change. There are 2 cables on the same side of the disconnect switch as the battery +, I just moved those 2 cables to the other side of the disconnect switch, that’s it.
 
Donzi98

Donzi98

Active member
WoodcarvingGypsy said:
I've noticed that there may be a parasitic drain on the batteries when the DC switch is turned off. Has anyone seen anything like this or is there something hooked in before the switch? I don't have the camper setting where it can be plugged in at the moment so I'm a bit concerned that the batteries will drain.

At some point, I will put a second disconnect in the line between the battery and the first buss bar. I'mn also going to put in a Thornwave monitor as well.

Observations and suggestions appreciated.
Click to expand...
Hi Al, what is a Thornwave monitor? Thank you.
Dave
 
bhidalgo

bhidalgo

Well-known member
With my solar panel and two Renogy Lithium batteries I don't seem to have any parasitic battery drain issues. Only issue I DO have is when I turn on the refrigerator a day before we go on a trip. I am luck to get 1 - 2 days of battery life when we do that. I already know I need a few more panels and a few more batteries. I wish this solar/battery situation was simpler to manage and get a handle on, but it is what it is. Love the challenge...sorta...LOL
 
Oregon_Camper

Oregon_Camper

Forum Moderator
Staff member
bhidalgo said:
With my solar panel and two Renogy Lithium batteries I don't seem to have any parasitic battery drain issues. Only issue I DO have is when I turn on the refrigerator a day before we go on a trip. I am luck to get 1 - 2 days of battery life when we do that. I already know I need a few more panels and a few more batteries. I wish this solar/battery situation was simpler to manage and get a handle on, but it is what it is. Love the challenge...sorta...LOL
Click to expand...
Personally, I would add more batteries before solar panels. Adding more solar only allows to fill your 2 batteries and then the panels do nothing. I like to have a LOT of power onboard and then use solar to add back. BTW...I will have 2,000 watts of solar added to our 340RL when we get it next month in addition to the 810 amp hours of Lithium Battle Born batteries. We boondock a LOT :)
 
Donzi98

Donzi98

Active member
Hi All,

There has been some pretty good discussion and ideas tossed around. I am still learning our trailers in and outs. We are taking her on her maiden camping trip next weekend. However, the battery is fully charged today. The battery switch is off. I bet there is more than parasitic current draw as when I put the battery back in, ( and the batt switch was off) there was a sizable spark connecting the cables up. This is a 650 CCA battery and it is draining down very quickly. I am guessing it will be dead before next weekend. My last trailer would go months in storage and the battery was good. What does the Alliance team say about this problem?

Thanks for the help everyone.

Dave
 
D

darrell

Well-known member
@Donzi98 I wonder if your battery disconnect switch is wired backwards where it is not actually switching the load off. My 2021 was wired backwards. It was an easy fix, just email Alliance and they should be able to provide pictures and instructions for it.
 
D

DanNJanice

Well-known member
darrell said:
@Donzi98 I wonder if your battery disconnect switch is wired backwards where it is not actually switching the load off. My 2021 was wired backwards. It was an easy fix, just email Alliance and they should be able to provide pictures and instructions for it.
Click to expand...
@Donzi98

What he said ^^^^
I checked mine and the disconnect does nothing. Everything DC is still powered no matter what position the switch is in. I will be tearing into that soon.

In the mean time I measured the parasitic draw on mine. The biggest draw is the invertor. Which, even when nothing is plugged in, draws 1-2 amps. If I turn off the invertor completely and make sure everything else is turned off, I can get the parasitic draw down to about 0.25 amps, which is fairly good. At that rate my batteries would last about 15 days before discharging below 50%.

If you do this kind of stuff very often you need a DC Clamp-on amp meter like this one. This is the one I have, it is fairly cheap and works well. The only downside to it is the clamp is almost too small to fit around the inverter cable.
 
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