Shore power and battery charger

The Rookie

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Looks as if my WFCO 8955 has ridden off into the sunset (it was on it’s last leg and this was expected).

My question is can I use an external battery charger while connected to shore power? And how will the BIM 160 react to the external charge?
 
Thanks Ace. The WFCO is still converting assuming since it’s still running the fridge brains, the charger has stopped. My new part is waiting at home for the install.
 
Thanks Ace. The WFCO is still converting assuming since it’s still running the fridge brains, the charger has stopped. My new part is waiting at home for the install.
That does not make sense since the converter and the charger are the same thing. Maybe the converter is producing 12 volts but not at a high enough level (13.5 or greater) to charge the battery.
 
That does not make sense since the converter and the charger are the same thing. Maybe the converter is producing 12 volts but not at a high enough level (13.5 or greater) to charge the battery.
Or there's a disconnect between the converter and the house batteries.
 
I was going with the some part that controls the charging output failed/is failing. It still powers the 12V systems I need at the moment.
Either way, I already have the replacement converter (went with powermax) and will finally joining the bus on LFP. The FLA house batteries are 4 years old and I do not believe they are holding charge or I suddenly have a hefty parasitic draw-more investigating to do once I return from our trip.

I appreciate the input from you both.
 
I was going with the some part that controls the charging output failed/is failing. It still powers the 12V systems I need at the moment.
Either way, I already have the replacement converter (went with powermax) and will finally joining the bus on LFP. The FLA house batteries are 4 years old and I do not believe they are holding charge or I suddenly have a hefty parasitic draw-more investigating to do once I return from our trip.

I appreciate the input from you both.
How many amps output is the new charger. I’m replacing my LA batteries with LFP and going with 60 amp charger. Existing ATS is fine so not gong with combined unit. Though about going with 100 amp charger but the unit is under the bed and thought increased heat and noise would not be worth the added charging. Thoughts?
 
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How many Amos output is the new charger. I’m replacing my LA batteries with LP and going with 60 amp charger. Existing ATS is fine so not gong with combined unit. Though about going with 100 amp charger but the unit is under the bed and thought increased heat and noise would not be worth the added charging. Thoughts?
Probably more info than you need, but good stuff to know...
 
Well, a little update:
Monday 730pm 12.65vdc at the posts
Tuesday 500pm 10.25 at the posts
Wednesday 700 pm 9.05 at the posts
And the chassis battery is also depleted (did not check volts)
I was able to determine there is a .85Vdc draw coming from somewhere.

Seems like new batteries all the way around. Any thoughts?
 
Well, a little update:
Monday 730pm 12.65vdc at the posts
Tuesday 500pm 10.25 at the posts
Wednesday 700 pm 9.05 at the posts
And the chassis battery is also depleted (did not check volts)
I was able to determine there is a .85Vdc draw coming from somewhere.

Seems like new batteries all the way around. Any thoughts?

There should be a large fuse or circuit breaker between the battery and the converter and I would find that and make sure it is not blown or tripped. Remember that many of the 12 VDC loads are wired in at the converter and fused there but the battery would need a much larger fuse/circuit breaker.
 
I was able to determine there is a .85Vdc draw coming from somewhere.

Seems like new batteries all the way around. Any thoughts?
Before buying new batteries (which it seems likely you will need sooner rather than later) I'd search for the source of the drain. Were you plugged into Shore Power? Was the Use/Store switch in the Use or Store position?

The CO/Propane detector is a measurable draw in RVs I've tested. Otherwise, with everything off the drain should be in milliamps. Radios will usually have a tiny draw to maintain the station presets.
 
There should be a large fuse or circuit breaker between the battery and the converter and I would find that and make sure it is not blown or tripped. Remember that many of the 12 VDC loads are wired in at the converter and fused there but the battery would need a much larger fuse/circuit breaker.
Thank you
 
Before buying new batteries (which it seems likely you will need sooner rather than later) I'd search for the source of the drain. Were you plugged into Shore Power? Was the Use/Store switch in the Use or Store position?

The CO/Propane detector is a measurable draw in RVs I've tested. Otherwise, with everything off the drain should be in milliamps. Radios will usually have a tiny draw to maintain the station presets.

Before buying new batteries (which it seems likely you will need sooner rather than later) I'd search for the source of the drain. Were you plugged into Shore Power? Was the Use/Store switch in the Use or Store position?

The CO/Propane detector is a measurable draw in RVs I've tested. Otherwise, with everything off the drain should be in milliamps. Radios will usually have a tiny draw to maintain the station presets.
Not connected to shore power, use/store was in Store position.
 
Did you mean .85 amp draw? Current flow is not measured in volts.
I’ll have to measure again then. I used my voltmeter, because my clamp meter only does AC (so the instruction manual says) and I was working in the storage lot. I
 
I’ll have to measure again then. I used my voltmeter, because my clamp meter only does AC (so the instruction manual says) and I was working in the storage lot. I
To measure with a non-clamp VOM you have to put the VOM into the DC amp range and likely move at least one of your test leads to the amp jack(s).

Then lift the combined ground (negative) lead from the battery bank and measure between the lifted lead and the terminal. Most VOM meters are limited to 10 amps when measuring this way.
 
Not connected to shore power, use/store was in Store position.
In that case if the batteries started out fully charged (~ 12.6V) they should have stayed fully charged for some time (days/weeks). Sounds like the batteries are kaput. They'll take a charge but can't maintain it. A load test would confirm they have failed. Many auto part stores (Auto Zone, O'Reilly's, etc) will load test batteries for free.

Are we sure the Use/Store switch is actually disconnecting the batteries? In the store position, none of the 12V items in the RV (lights for example) should work.
 
Before buying new batteries (which it seems likely you will need sooner rather than later) I'd search for the source of the drain. Were you plugged into Shore Power? Was the Use/Store switch in the Use or Store position?

The CO/Propane detector is a measurable draw in RVs I've tested. Otherwise, with everything off the drain should be in milliamps. Radios will usually have a tiny draw to maintain

In that case if the batteries started out fully charged (~ 12.6V) they should have stayed fully charged for some time (days/weeks). Sounds like the batteries are kaput. They'll take a charge but can't maintain it. A load test would confirm they have failed. Many auto part stores (Auto Zone, O'Reilly's, etc) will load test batteries for free.

Are we sure the Use/Store switch is actually disconnecting the batteries? In the store position, none of the 12V items in the RV (lights for example) should work.
I agree that the batteries are done. As for the use/store switch, I always Leave a light on to visually see the power cut off when I push to the store position.
 
To measure with a non-clamp VOM you have to put the VOM into the DC amp range and likely move at least one of your test leads to the amp jack(s).

Then lift the combined ground (negative) lead from the battery bank and measure between the lifted lead and the terminal. Most VOM meters are limited to 10 amps when measuring this way.
When you say combined, is that the same as ground to chassis? If so, that is how I measured it, just used the ground incorrect VOM setting.
 
When you say combined, is that the same as ground to chassis? If so, that is how I measured it, just used the ground incorrect VOM setting.
Yes, when you have multiple batteries in parallel the negatives are combined and a single cable goes to the chassis ground connection.
 

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