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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Sebulba on December 25, 2021, 12:25:32 PM

Title: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 12:25:32 PM
Hello all,

We will be sitting for about 4 months and am wondering about suggestions for a battery tender for the bus batteries.

Also, would it be advisable to get 2 battery tenders (12 volt), one for each battery?

Thanks

Seb
Title: Re: Suggestion for a battery tender
Post by: richard5933 on December 25, 2021, 12:36:22 PM
My 24v bus battery bank (two 12v 8D batteries in series) has been on a Progressive Dynamics 24v converter/charger for years. This is a true multi-state unit which will keep the batteries well.

I've always been leery of 'battery tenders' as they are often not smart systems and only have one, constant voltage output.

This is the unit I have: https://www.progressivedyn.com/specialty/pd9240-24a-volt-power-converterbattery-charger/

Title: Re: Suggestion for a battery tender
Post by: chessie4905 on December 25, 2021, 02:00:40 PM
Battery tenders may not be able maintain large batteries or ones that are older condition. Automatic smart charger?
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 02:42:58 PM
Quote from: richard5933 on December 25, 2021, 12:36:22 PM
My 24v bus battery bank (two 12v 8D batteries in series) has been on a Progressive Dynamics 24v converter/charger for years. This is a true multi-state unit which will keep the batteries well.

I've always been leery of 'battery tenders' as they are often not smart systems and only have one, constant voltage output.

This is the unit I have: https://www.progressivedyn.com/specialty/pd9240-24a-volt-power-converterbattery-charger/

Thank you, I will look into that.

Seb
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 02:44:39 PM
Quote from: chessie4905 on December 25, 2021, 02:00:40 PM
Battery tenders may not be able maintain large batteries or ones that are older condition. Automatic smart charger?

Maybe.  I do have a 10 amp 12 volt charger?

Seb
Title: Re: Suggestion for a battery tender
Post by: Van on December 25, 2021, 03:00:31 PM
Heres ours
https://www.impactbattery.com/24-volt-40-amp-on-board-charger-quick-charge.html
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 03:27:35 PM
Quote from: Van on December 25, 2021, 03:00:31 PM
Heres ours
https://www.impactbattery.com/24-volt-40-amp-on-board-charger-quick-charge.html

That looks like a nice unit.  Maybe a little more than I am looking for right now.

Thanks

Seb
Title: Re: Suggestion for a battery tender
Post by: buswarrior on December 25, 2021, 06:35:22 PM
I like the Noco Genius chargers.

Smart, reasonable price.

I watched the old 3/4 amp one work over a bad car battery. Multimeter on it to watch the voltage go up and down over 3 days, the circuitry had decided it needed equalization. Kissed 15 volts, voltage dropped to normal tending, and got the steady green light.

Battery returned to service.

For the coach, if it is "in storage" and not fully equipped electrically yet,  a 12 volt smart tender on each battery solves/prevents/defends against whatever evils pairing them up might cause/contribute/continue.

And cost effective, initially and later they can be used on all the rest of your 12 volt equipment

Happy coaching!
Buswarrior
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 07:10:39 PM
Quote from: buswarrior on December 25, 2021, 06:35:22 PM
I like the Noco Genius chargers.

Smart, reasonable price.

I watched the old 3/4 amp one work over a bad car battery. Multimeter on it to watch the voltage go up and down over 3 days, the circuitry had decided it needed equalization. Kissed 15 volts, voltage dropped to normal tending, and got the steady green light.

Battery returned to service.

For the coach, if it is "in storage" and not fully equipped electrically yet,  a 12 volt smart tender on each battery solves/prevents/defends against whatever evils pairing them up might cause/contribute/continue.

And cost effective, initially and later they can be used on all the rest of your 12 volt equipment

Happy coaching!
Buswarrior

Great!  That's more like what I'm looking for now. 

Thanks for your input.

Seb
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 07:16:38 PM
Quote from: buswarrior on December 25, 2021, 06:35:22 PM
I like the Noco Genius chargers.

Smart, reasonable price.

I watched the old 3/4 amp one work over a bad car battery. Multimeter on it to watch the voltage go up and down over 3 days, the circuitry had decided it needed equalization. Kissed 15 volts, voltage dropped to normal tending, and got the steady green light.

Battery returned to service.

For the coach, if it is "in storage" and not fully equipped electrically yet,  a 12 volt smart tender on each battery solves/prevents/defends against whatever evils pairing them up might cause/contribute/continue.

And cost effective, initially and later they can be used on all the rest of your 12 volt equipment

Happy coaching!
Buswarrior

Let me ask, to tend the batteries, how many amps do you think is enough?

Thanks

Sen
Title: Re: Suggestion for a battery tender
Post by: richard5933 on December 25, 2021, 07:25:23 PM
If you are going through the effort to install a 'tender', why not just install something robust enough to actually charge them when you need?
Title: Re: Suggestion for a battery tender
Post by: windtrader on December 25, 2021, 07:45:49 PM
I don't see using a regular charger than is connected to a timer. Seems like x minutes every x days would do just fine. Not all that scientific but if just trying to keep the battery tickled and in the voltage range, seems like nearly zero cost if a charger is lying around.
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 07:52:47 PM
Quote from: richard5933 on December 25, 2021, 07:25:23 PM
If you are going through the effort to install a 'tender', why not just install something robust enough to actually charge them when you need?

That is worth considering. 

Sen
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 25, 2021, 07:55:21 PM
Quote from: windtrader on December 25, 2021, 07:45:49 PM
I don't see using a regular charger than is connected to a timer. Seems like x minutes every x days would do just fine. Not all that scientific but if just trying to keep the battery tickled and in the voltage range, seems like nearly zero cost if a charger is lying around.

I do have a good 12 volt charger, but that would only do one battery.

The ones that BusWarrior mentioned had double charger options.  I assume that they would equalize and do a good job of maintaining.

Seb
Title: Re: Suggestion for a battery tender
Post by: luvrbus on December 26, 2021, 05:28:45 AM
Charge the batteries to full charge disconnet the cable and you will fine for 4 months with no draw from the batteries, I am not a big fan of battery maintainers on lead acid batteries all they do is keep the voltage up .I replaced a NAPA G-27 battery the green lights said it was ok lol it wouldn't even start a lawn mower if you tried much less the generator 
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 26, 2021, 05:47:38 AM
Quote from: luvrbus on December 26, 2021, 05:28:45 AM
Charge the batteries to full charge disconnet the cable and you will fine for 4 months with no draw from the batteries, I am not a big fan of battery maintainers on lead acid batteries all they do is keep the voltage up .I replaced a NAPA G-27 battery the green lights said it was ok lol it wouldn't even start a lawn mower if you tried much less the generator

Thanks, I thought ofusing the disconnect switch.  Essentially the same as disconnecting the batteries, I think.  When I have used that in the past, the DDEC seemed to not start.  What I mean is the display is dead and I don't have turn signals and some other things didn't work until I started the bus again.

I attributed this behavior to disconnecting the battery.  So, am trying not to do that any more than needed.

My diagnosis may be faulty, but that's what I came up with.

Input?

Seb
Title: Re: Suggestion for a battery tender
Post by: luvrbus on December 26, 2021, 05:53:38 AM
The DDEC has a tiny draw even with the disconnet off.the DDEC has it's own battery also,I disconnet all the cable then when ready hook those back and fire it off after months of setting   
Title: Re: Suggestion for a battery tender
Post by: Sebulba on December 26, 2021, 06:05:18 AM
Quote from: luvrbus on December 26, 2021, 05:53:38 AM

The DDEC has a tiny draw even with the disconnet off.the DDEC has it's own battery also,I disconnet all the cable then when ready hook those back and fire it off after months of setting

OK, interesting. 

I wonder why the DDEC had problems after battery disconnect?  Could the DDEC battery be bad?

I can clarify why I was disconnecting the battery.  When we bought the bus a month ago it came with no locks or keys, so when we stopped at a store or left the bus for some reason I would use the battery shut off as a theft deterrent.  Since then I have gotten door locks and keys, so am no longer doing that. 

Since not using the battery disconnect, the DDEC always works.  It seems that there was a connection between using the shutoff and the DDEC not functioning.

Another thought.  I would turn the battery disconnect switch on and then start the bus like a minute or 2 later.  Could it be that I should have waited longer after turning the switch on to allow for boot up?

Thoughts?

Thanks

Seb   
Title: Re: Suggestion for a battery tender
Post by: Jim Blackwood on December 26, 2021, 06:11:12 AM
Seb, your bus will have a bypass of the main disconnect that powers the Vanner for battery equalization. Check it by looking for a tiny spark when the battery cables are reconnected. To disconnect entirely you need to pull both the B+ and B- cables (the short bridge cable can stay)

I have yet to decode the complete functions of the Vanner but apparently MCI felt it was required.

Jim
Title: Re: Suggestion for a battery tender
Post by: luvrbus on December 26, 2021, 06:46:49 AM
Disconnet the bridge cables too it seems to work better  than leaving 2 batteries tied together
Title: Re: Suggestion for a battery tender
Post by: sledhead on December 26, 2021, 08:26:55 AM
I put a latching relay switch on the 24v side and nothing would go through
( total disconect ) and never had a problem with the DDEC or the vanner having no power when the disconect was used
I did the same thing for the house side as well

on the MCI

dave