Can you charge through a Vanner?

[justin25taylor]

Both of my coaches have 12V systems as they are Eagles. So I am not familiar with them. I do drive Prevost entertainers though and they use them to feed some of the 12v systems on the coach. Just to satisfy my curiosity, is it possible to send 12v from say a small charger to the Vanner to maintain the 24 volt battery bank while in storage?
It may be common sense, I dont know.

Sorry if the question is stupid.

Justin

[bevans6]

I am pretty sure Vanner's won't do that, although there are other equalizers that will.

Brian

[Sean]

Some equalizers are bidirectional, meaning they can take charge from the 12v side and move it to the 24v side as well as the (more common) other way around.  As Brian writes, most Vanners are unidiectional and can only move charge from the 24v side to the 12v side.

That being said, there is a way to use a 12v charger with this type of equalizer, which is to connect it to the upper battery, IOTW, between the center post and the 24v post.  The Vanner will see this as an imbalance and will move power from the 24 side back down to the 12v side.  Obviously with this method, the charger must be a lower amperage than the rating of the Vanner.

There is a caution here.  For this to work, the charger must have a fully isolated output.  If the DC negative of the charger is connected to ground inside the charger case, which is in turn grounded through the charger's AC input, then connecting the charger's negative output to the battery center post will cause a short.

HTH,

-Sean
http://OurOdyssey.BlogSpot.com

[justin25taylor]

Got it guys. Thanks.
Sean, Never thought about ground issue...
I will just put an smaller Iota 3 stage 24V charger on there for them. They just wanted something on that bank to keep batteries topped off during storage, or in case some coach related accessory was left on.
House bank is 12V so I cant just use the charger from there. They have a separate 12V alt for the house batteries. Kind of a dumb setup, but I can't take credit for the work the conversion co. did. 

Thank you both

[buswarrior]

Good idea!

When it comes to an entertainer coach, you can be sure the batteries will go dead if left engaged and unattended.

And, for the unknowing, you can't just pull the battery disconnect...

Disconnecting the batteries starts an entirely different set of headaches: getting every stored preset and clock in the coach, on every device, re-set. Multiple radios, VCR's, satellites, televisions, clocks, and who knows what else...

way too much circuitry, designed and executed by the devil's henchmen.

Ever wonder where the old entertainers disappear to?
There is a fleet of them in Hades for the unforgiven busnuts to work on...

happy coaching!
buswarrior

[justin25taylor]

Good idea!

When it comes to an entertainer coach, you can be sure the batteries will go dead if left engaged and unattended.

And, for the unknowing, you can't just pull the battery disconnect...

Disconnecting the batteries starts an entirely different set of headaches: getting every stored preset and clock in the coach, on every device, re-set. Multiple radios, VCR's, satellites, televisions, clocks, and who knows what else...

way too much circuitry, designed and executed by the devil's henchmen.

Ever wonder where the old entertainers disappear to?
There is a fleet of them in Hades for the unforgiven busnuts to work on...

happy coaching!
buswarrior

BW,
You nailed it pal. This rig is not mine and I seldom see it unless there is a problem 

They keep it plugged in and the "house" side stays maintained nicely by the inverter while not in use. Running down the road they keep genset running 24/7 so the driver can collect generator service fee, instead of using the very nice inverter and bus air they have. At venue they are plugged in or running generator.


The problem is the "Chassis" battery bank. It is 24 Volt and with the DDEC and other small drains it needs a little help when unused. As you said, hitting the disconnect only disconnects "most" of the loads. The loads that do not pass through the disconnect can leave the battery bank flat in a couple weeks.
I ordered a 24V Iota 3 stage charger to install and that should end their problems.

Last summer, I installed a pair of 8D AGM batteries for the house side so they could run 24V refrigerator(s) overnight without generator if staying in a hotel or parking inside a venue w/o shore-power (where generator use is a no-no).
They seem to be OK so far and the charger is holding the float voltage within one or two hundredths of the "float voltage" recommended by battery manufacturer. I have limited experience with AGM's so I hope a couple hundredth's of a volt is "close enough"  I ran both refrigerators overnight and all morning today and I am showing about 30% DOD per Pro link. I am going to let them sit a while longer with no charging and no load and check resting voltage again to make sure all is well.

Sure wish you could use hydrometer on AGM batteries. I may be over worrying though, if these last more than a year or so they will last twice as long as the GC batteries they had been using lasted.
Driver will NOT check/water batteries so I am hoping AGM solves the problem for them. I may suggest AGM start batteries the next time they fail if I find them dry.
I hope the new Iota float voltage works well with flooded starts. Mfg. rep says yes. Time will tell.

Thanks for the help and sorry for the long post.

Best,
Justin

[buswarrior]

Thanks justin.

Thanks for sharing, and it sounds like you are doing a great job for them.

The side education is priceless.

You don't learn anything when things go well....

happy coaching!
buswarrior