MasterVolt Combi - Equalise charge mode

[nicknorman]

2 hours ago, Mike55 said:

Thanks for that. But why would the cell have such a high SG reading (1.3)?

How is you check the sg? If using a floaty thingy did you remember to correct for temperature? sg will be higher or lower depending on the volume of electrolyte in the cell so if the level is low the sg will be high. But I don’t really like the sound of the brownish colouration, something not right.

 

But anyway, the advice from Trojan is only to equalise if any cells are below 1.250 or there is more than 0.030 difference. So if your lowest cell is 1.250 then no need for further equalisation (discounting the 1.30 which is abnormal).

[Mike55]

1 hour ago, nicknorman said:

How is you check the sg? If using a floaty thingy did you remember to correct for temperature? sg will be higher or lower depending on the volume of electrolyte in the cell so if the level is low the sg will be high. But I don’t really like the sound of the brownish colouration, something not right.

 

But anyway, the advice from Trojan is only to equalise if any cells are below 1.250 or there is more than 0.030 difference. So if your lowest cell is 1.250 then no need for further equalisation (discounting the 1.30 which is abnormal).

Yes, I did use a floaty thingy, although you're right, I didn't make a temperature correction. At the time I was more concerned about differences between cells, and as all the readings were taken at the same time, temperature was unlikely to affect that.

 

I've now left the batteries disconnected and will monitor how quickly they self discharge. If the 1.3 cell has a short then hopefully that will show up.

Edited September 25, 2022 by Mike55

[cuthound]

20 hours ago, Tony Brooks said:

 

Because it is indicative of the plates shedding their material and that will build up in the sediment traps at the bottom of the cell and cause a short circuit.

 

 

 

For the OP's clarification muddy brown or a blackish electrolyte colour is indicative of plate shedding but chocolate brown positive plates are a sign of a charged battery.

 

Also the 2% or less tail current is only a reliable indicator of fully charged at absorption, bulk or equalisation voltages (14.6 volts or higher for a 12 volt battery). His 1% tail current at float voltage is not a good indicator of a fully charged battery.

Edited September 26, 2022 by cuthound
Clarification