Battery connect or disconnect?

[AIR-Quarius]

Recently a fellow RV'er was helping me replace the seals in my wheel bearing area and take care of that business. As we discussed other 'to-dos' around the Airstream, he said to leave the battery connected or hooked up while I was hooked up to power. I am not sure of this as the former owner told me to dis-connect it. The P.O said if left hooked up - the battery would continue to charge and could damage it. It's a large battery at that. So to be on the safe side I am going to disconnect it today. What are your opinions? I will be watching my emails for you response. Thanks, Bill

[dznf0g]

Depends on what converter you have. Search 3 stage converter and a lot of info will come up. Long story short, a Univolt or any other single stage converter may damage your batts over the long haul. A quality 3 stage will not.

[AIR-Quarius]

Is the power/breaker box where my fuses are ---is this the converter?

[dznf0g]

I'm no expert on the older units....I'll let others say definitively. But, look for either glass tube or automotive blade fuses. That's your 12V fuse box. I seem to recall some fuse boxes were built into the converter assembly. Perhaps you could post some pics?

If you trace the battery cable from the batts back, you should find they are hooked to (probably) a positive and negative junction block, and the blocks will have wires running to the converter.

[AIR-Quarius]

The fuses are glass 'blade type' 20 volt...but I will take a closer look today and take a photo of whats in there. Thanks everybody else keep chiming in.

[Wingeezer]

We have the original converter/charger that came with our trailer. My understanding is that it is not a "smart" charger. I have AGM batteries That I installed a couple of years ago and hoping to prolong their life, I have gotten in the habit of disconnecting the batteries whenever we are staying someplace on shore power for more than a couple of days.

I use those quick disconnect knobs right on the battery terminals, but I suppose it would be easier just to identify the feed wire from the charger and put a switch in it. I should look into that!

Brian.

[Bigskyrider8]

I don't trust my one stage converter at all, I always leave the batteries disconnected from the system (by keeping the use/store switch in "Store".
When at home, I connect my 8 amp $30 dollar trickle charger to the batteries to top them off.
I have a Progressive Dynamics multi-stage converter on order, but I think I'll wait to exchange it with the one that's now onboard.......after the coach warranty expires.

[Al and Missy]

If the schematic in the manual is to be believed, on my trailer (2001 Safari 25) the disconnect switch disconnects the feed to the fuse panel from the battery and converter. The converter is always connected to the battery. It seems to work that way too. Even when connected to shore power, if I throw the disconnect switch, all 12V circuits go dead. I just installed a PD9260 to preserve my new battery.

If you believe you are disconnecting the battery from the converter with the disconnect switch, it would be worth a test to verify that fact.

Al

[Wingeezer]

I agree with Al's comments to check what happens to your battery when you use the "store" switch - I'm not sure quite what that thing does!

When we first got our trailer, my assumption was that the store switch disconnected the coach batteries from anything in the trailer - but that is not so.

I found that with shore power disconnected and the switch in store position, there was still a significant current draw from the batteries.

I did not measure it but it was enough of a draw to throw a significant spark when you touch the battery cables to the terminals. Seems strange. That is why I disconnect my batteries completely when on shore power more than a few days and also when I put our trailer in storage.

As a test, when on shore power, you could measure the voltage on your battery terminals, then throw the store switch to store position and recheck the voltage at the batteries again.

If it drops from maybe 13.4 volts to something in the 12's when you do that, then your charger is disconnected by throwing the switch.

One of these days I will try to figure out what that store switch does, for now, I just never use it!!

Brian.

[Al and Missy]

Sparking when connecting the cables is probably just charging up capacitors in the converter and does not represent much of a constant drain. The only way to know for sure is with an ammeter. The propane detector is supposedly connected directly to the battery, but only draws about 1/4 amp if I remember correctly. That wouldn't cause much of a spark, but will drain a group 27 battery in a couple of weeks. So much for the "storage switch"!

[Wingeezer]

Al - good point about the capacitors, never thought of that - but if so, I guess that confirms that the converter /charger is still connected to the battery when the store/run switch is in the store position.

The wiring of that switch - however it is wired - seems a bit counter intuitive - I would have thought it would just cut the batteries out completely. Not so in mine anyway unless it is defective!


Brian.

[Bigskyrider8]

Check the owners manual, it's detailed and I'm sure written by a group of electrical engineers that designed the system......lol. Strange that we, as owners have to guess and fumble our way through all of this.