Hi,

I need to record some information about the state of my off-grid power supply batteries which are 2VDC 1200Ah. I want to gather the Amps, volt & temperature of each battery and assumed there would be loads of really cheap sensors to do this.

Alas that is not the case. Therefore I have to start making them myself and yes I am a newbie to Electronics (and old to boot). I have searched high and low for circuits that I can copy but think I am getting bogged down.

As the batteries fluctuate in Voltage and Amperage especially when being de-sulphated once a month I need senors that are rugged enough to support high fluctuation.
Can anyone please in realy simple terms tell me how to make a voltage sensor circuit and an amperage sensor circuit. The results will be fed into an Arduino for data logging etc.

I had though to use a a multiplexer ic to switch to the sensor required as over time I will need to add Specific Gravity and Temperature for each battery so that would be at least 4 sensors for each battery x 24, So i pcb with each sensor linked to a multiplexer would reduce wires and leave room for expansion.

Just to finish off I am disabled and partially sighted after an accident which is one of the reason for wanting to have a readout indoors rather than hobbling around the batteries all the time.

Thank you in advance to anyone who can help me.

kind regards,

jB

 

I have the luxury of already having a LabJack U3HV for data acquisition. Assuming you have an old computer you could use, your project would be simple with this device. You would control the LabJack directly from within Excel, or you could use any programming language you like. I just prefer Excel because as soon as I have the data, all the data-manipulation and charting tools of Excel are readily available and I don't have to code them.

The LabJack measures voltage directly, so a wire to each cell. For current, you'll probably want Hall sensors as these are non-invasive. Temperature can be measured with a LM35 thermometer IC, which will convert temperature to voltage for the LabJack to read. The LM35 needs to be powered, but the LabJack can supply that directly.

BTW, the LabJack supports protocols that would allow you access it remotely from anywhere on the internet.

 

Hi,
Thanks for the steer.
I'll see what a LabJack is, but my quest for circuits goes on...
jB