Battery Break in Question

[JMGreco]

Johnnie,

Good morning, voltage after full charge and in float cycle this morning is 52.7. Checked voltage with different DVM and voltage is 52.7. Double checked DPI charger setting an confirm it is set to Mode 1. Individual battery reads durning float as follows;

8.80
8.79
8.74
8.83
8.78
8.73

I am wondering if the set is from two different production runs? All batteries have K3 Z stamped on the positive posts. Thinking of trying to bring the lower readings up on 6v charger?

[JMGreco]

Scrap that last thought, just remembered I am now 8v not 6v

[JohnnieB]

Originally Posted by JMGreco

Johnnie,

Good morning, voltage after full charge and in float cycle this morning is 52.7. Checked voltage with different DVM and voltage is 52.7. Double checked DPI charger setting an confirm it is set to Mode 1. Individual battery reads durning float as follows;

8.80
8.79
8.74
8.83
8.78
8.73

I am wondering if the set is from two different production runs? All batteries have K3 Z stamped on the positive posts. Thinking of trying to bring the lower readings up on 6v charger?

I believe your batteries are not being fully charged. Of course, I might be wrong, but you have about a grand invested in the new batteries and charger, I suspect you want to find out for sure.

The six 8V batteries are being charged in series, so the charger only sees the sum of their voltages, which is 52.67V. The information I pried out of DPI a while back was that in Mode-1, a DPI Accusense 36V charger floats at 39.80V. A 36V pack has 18 2V cells, so that is a little over 2.21VPC and a 48V pack has 24 2V cells, so that works out to 53.07V.

The only hard numbers I have for Float charge are for 36V in Modes 1, 2 & 3
(Us Battery, Trojan & Exide) which are 39.80V, 39.40V & 39.60V respectively. However, using the same logic, the calculated Float voltage for my 42V Exide pack is 46.2V and my pack typically floats at 46.4V or 46.5V, so I'm fairly confident a 48V pack of US Battery batteries should float at 53.1V or a bit higher rather than 0.4V lower.

I do have hard numbers for the VPC (Volts per Cell) for the absorption phase in all four modes. For US Battery it is a minimum of 2.5VPC, or 60.0V for a 48V pack.

The charger is in the absorption phase when the Yellow LED is on steady and the Ammeter has dropped below the Max Amp rate.
What is your pack voltage after the Ammeter drops down to 5 to 8 amps?

Also, what is the pack voltage after the charger has been disconnected from the cart for about 12 hours?
(Should be at least 51.19V, probably a bit higher since they are new)

[JMGreco]

Tire rod end broke in the back yard this afternoon so done with cart today and on the charger.

Charging with charger at 5 amps I am at 63 volts.

I removed all feeds to the pack ( voltage reducer, on board digital volt meter, reed swith by-pass power) and only have the high voltage loop and charger leeds connected to the pack.

Will check voltage when in float stage with hand held DVM and will report back.

[JMGreco]

Now floating at 53.4, will continue to monitor.

[JMGreco]

Floating at 52.7

[Sumner121]

I have a 94 club car and am only on day two of my 48 volt conversion which means my second charge. Love the difference! However with Trojan batteries and a DPI charger I am getting the same reading 52.8 after about 45 minutes of the green light being on. The DPI chargers are factory programmed to mode 2 right?

[JMGreco]

Yes, Mode 2 is for Trojan and it is the factory setting.

[720Deere]

Sorry to hear about the tie rod, Joe. You must have been giving her a good workout! I got tied up building a retaining wall today so we couldn't make it over to check it out. Sounds like I didn't miss much after all.

[JMGreco]

Matt - no worries. I am glad it happened at home instead of on one of extended road rides. Hope C&C has one in stock, should be a quick fix, then will use SportCoupe's alignment method. We have a full weekend next week but will let you know when things calm down.