Hi,
Apparently a leisure battery is fully charged at 12.7v, 75% charged on 12.4v, 50% charged on 12.2v, 25% on 12v with 11.9 fully discharged. Spring have advsied that at leisure battery can go to a lower voltage than than, and have a new analogue controller out by the end of this month that cuts out at 10.5v
Spruce
I was always told that the battery voltage could read lower than those levels if you test it whilst in use or very shortly after use? After a couple of mins the voltage will rise slightly to give the levels you've mentioned. It was a mechanic that told me, I thought it sounded sensible, but I never checked up on it.
Thanks for the input Spruce and Nat.
Cliff the controller you have has a battery voltage monitoring system and Voltage meter. the voltage displayed is measured at the controller - not the battery. It is likely that your battery will show a higher voltage than displayed on the controller. This difference on the whole is down to volt drop and resistance along the cable.
12.4 shown at the control is a good level - The battery will likely show a higher voltage if tested with a volt meter.
The controller has a low battery warning and shout down.
If the voltage at the controller is measures at 11.5V or less you will see the warning BAT displayed on the control.
Once the controller detects 11V or less it will shut down the pump you will see the BAT message flash along with voltage displayed.
As Spruce says battery manufacturers will give different rates as to when a leisure battery is discharged - as a general rule the battery will run lower hence our cut off at 11V without to much risk to the battery. That said the more often the battery is run low the more likely damage to the cells may occur.
Also as Nat says take the load off the battery by switching off the pump and the voltage level will rise slightly.
The difficulty for us has been how to read a more accurate voltage at the battery while its under load.
We have solved this issue with the new V11 analogue and are able to get a very accurate reading on the battery voltage. This and comments from cleaners mean we have reduced the cut off value to 10.5V.
