Battery removal

[Gene Obie]

I need to disconnect and remove the house batteries and do some work on battery tray prior to installing new batteries. I have Xantrex SW2512 inverter and it states the inverter must be off with no external AC input when connecting and disconnecting the batteries. The coach battery isolation switch also has the warning not to turn off the chassis battery isolation switch with AC connected.

Question is: Once i turn off shore AC and disconnect the batteries can I re-enable shore power AC and turn the inverter ON? I'm living full-time in the coach and it will probably take me some time to get battery tray work done and new batteries installed. Not sure at this point if I can just clean it up and restore or whether the tray will need to be replaced.

Thanks

[Fred Brooks]

   Gene,
My suggestion is this. Turn off the inverter at the remote panel. Turn off the 120 volt circuit breaker marked inverter/charger in the bedroom. Cable tie all cables together going to each respective battery post and add labels with masking tape. Take multiple pictures with your phone. Remove the batteries and tray for reconditioning. If long term, find a way to reinstall the batteries safely on crates or some fabricated means to support them. When you reconnect the cables, you will get a large spark with the last connection. (This is normal, you are powering up a large capacitor inside the inverter/charger). Turn on the circuit breaker, the charger will automatically resume its charging sequence. Hope this helps, Fred

[Gene Obie]

So Fred, to clarify I think you are telling me that I can't run the inverter and have 120V in the coach unless I have at least one 12V house battery connected? If that's true then maybe I will just power down and remove the batteries and tray as you say and temporarily install only 2-6V  batteries (I have 6-6V total) then power inverter back up while I"m working on tray and new batteries & cabling.

[Adam Hicklin]

I’ve seen this type of question before and it’s always confused me.  If you’re connected to shore power, why would the inverter need to be on?

[Mike Shumack]

So Fred, to clarify I think you are telling me that I can't run the inverter and have 120V in the coach unless I have at least one 12V house battery connected?

The reason may be this:
This snippet is from the Xantrex manual, yours may be the same.

[Fred Brooks]

   Gene,
 Mike is correct and thank you for that quote. When the inverter/charger sees 120 volts from shore power, it is no longer an inverter! it is only a battery charger. It analyses the current state of charge in the house batteries and then proceeds to charge either bulk, absorb or float charge until satisfied.
   Yes Gene, you can reinstall 2 of your 6 volt batteries in series (12 volts). When on shore power, the charger will provide all the 12 volt you need to operate. Good luck on the tray! not a fun job but very satisfying when complete. Fred

[Gene Obie]

A follow-up to this after checking my system behavior it seems my inverter is a little different. My Xantrex manual doesn't have the comment Mike referred to.

My inverter has OFF, ON and CHG settings on the panel

OFF: I get no AC in the coach, regard of whether shore power or generator is present (confirmed by discharging batteries then turning on shore power and measuring current and volt at the batteries). So the inverter must be ON or CHG to get AC in the coach or to charge the batteries.

ON: AC in coach and battery backup if shore power is lost. Batteries set up to charge if AC present and discharge if no AC.

CHG: AC in coach and no battery backup if shore power is lost. Batteries only charge and dont' discharge.

Also, I now realize my AC units do not operate if there is no 12V power, same with entertainment system (for some reason).

So in the end I will just attach one 12V battery bank and keep the inverter in "ON" while I rework the system.

[Fred Brooks]

    Gene,
If you have a SW2512 inverter/charger I believe it is a "Trace" which was bought by Xantrex. Make sure you unplug the coach, turn the inverter off, and throw a blanket over any solar panels. After battery and tray removal, go ahead and install the 2-6volt batteries and cables and proceed as you stated. Confirm that your remote looks like this:

[Gene Obie]

Fred, good catch on the solar panel. And yes my remote looks like your pic. Now I see the remote is only active when DC power is applied. So since I get no AC without turning on inverter, and get no power to the remote without DC that pretty much confirms I need batteries installed for my system to work at all on external AC power. It would see to follow then if I blow one of those DC battery fuses I'm dead in the water with loss of all power until I replace the fuse.


Don't know the history on the naming but my manual lists both names in big letters. Trace is listed as a trademark as well as Xantrex Technologies Inc.