12 V to 24V...battestionry charger que

msgieser

If I upgrade a 12 volt system to 24 volts, is there any way to still use my 12 volt battery chargers? I have two 75 amp, generator powered chargers that I use for battery charging on "low solar" days. Can two 12 volt chargers be combined in any way to still use them on a 24v bank?

Cariboocoot

Re: 12 V to 24V...battestionry charger que

Yes you can, but only for Bulk charging. The chances of them charging each half of the 24 Volt bank equally is not very good.

vtmaps

Re: 12 V to 24V...battestionry charger que

msgieser wrote: »

If I upgrade a 12 volt system to 24 volts, is there any way to still use my 12 volt battery chargers? I have two 75 amp, generator powered chargers that I use for battery charging on "low solar" days. Can two 12 volt chargers be combined in any way to still use them on a 24v bank?

You need to make sure the charger outputs are floating with respect to ground, otherwise you will be putting a short circuit across one of the batteries.

--vtMaps

msgieser

Re: 12 V to 24V...battestionry charger que

Ok Coot....I presently just use them for bulk charging anyway. If I have two banks of six volt batteries set up for 24 volts, each 12 volt, 75 amp charger could handle each group of four batteries????

ytmaps....showing my ignorance here....but just what do you mean....charger outputs are floating with respect to ground. In my present 12 volt set up, all negative battery connections (neg from controller, neg from battery charger, neg from monitor, neg to inverter) go to the shunt, out of the shunt is the only thing going to the battery negative.

Cariboocoot

Re: 12 V to 24V...battestionry charger que

msgieser wrote: »

Ok Coot....I presently just use them for bulk charging anyway. If I have two banks of six volt batteries set up for 24 volts, each 12 volt, 75 amp charger could handle each group of four batteries????

Would be connected to four batteries: two parallel sets of two in series.
Now here's an issue: there probably is not (nor should there be) a connection between the two strings at the midway (12 Volt) point. So you either do one 24 Volt string at a time or make a connection at that point. Either can be problematic.

ytmaps....showing my ignorance here....but just what do you mean....charger outputs are floating with respect to ground. In my present 12 volt set up, all negative battery connections (neg from controller, neg from battery charger, neg from monitor, neg to inverter) go to the shunt, out of the shunt is the only thing going to the battery negative.

This is unlikely to be an issue with stand-alone AC powered chargers as the negatives are usually not connected to ground or either side of the AC input.

BB.

Re: 12 V to 24V...battestionry charger que

msgieser wrote: »

ytmaps....showing my ignorance here....but just what do you mean....charger outputs are floating with respect to ground. In my present 12 volt set up, all negative battery connections (neg from controller, neg from battery charger, neg from monitor, neg to inverter) go to the shunt, out of the shunt is the only thing going to the battery negative.

We try to be careful when making generic recommendations. Most automotive and standalone battery systems are either negative grounded or floating outputs.

When you put a pair of 12 volt battery chargers on a 24 volt battery bank, the first (negative) connection is at zero volts (relative to ground), the next is +12 volts. For the second charger its "negative lead) is at +12 volt and the positive lead is at +24 volts relative earth ground.

Since there are more "12 volt battery chargers" than any of us could possibly know about--Just a warning to make sure that the output of the battery charger is floating relative to its "earth ground" (if the plug is three wire) so that you don't get a "surprise" when connecting up the battery bank to your 12 volt battery charger.

Most are floating outputs--But some industrial/larger/specialized battery chargers could conceivably have a ground referenced output.

-Bill

westbranch

Re: 12 V to 24V...battestionry charger que

Noah, your link does not work...

Cariboocoot

Re: 12 V to 24V...battestionry charger que

westbranch wrote: »

Noah, your link does not work...

Especially after I banned the link spammer.