Hi to all, this is my first post. I look for a presentation section but I din't find it. If it's mandatory I promise to do it as soon is possible.



I need to monitor no-load current absorption on a 12vcc equipment with about 40 channel. 3-4 read per seconds for 24hour monitor.

Maximum current value is 30A. Someone can kindy tell me if theres any device who can do this job?

 

Presumably you have a microcontroller, so if we work backwards from there.
There are plenty of multichannel A/D converters, which you can combine to produce 40 channels. They will need 0 to 5V inputs, so we have to produce a suitable signal from the current detectors.
Your maximum current is 30A - is that 30A per channel?
What is the minimum current you need to measure?
Is 30A the on-load current? If you need to measure NO-load current, do you also need to measure on-load current? If not, then presumably you could ignore any current above, say, 1A?

 

Hi Ian0.
I'm not interested about "on-load" current. I'm asking if there is already an instrument data logger multichannel to do that. Otherwise I have to open a new post about how to make this device.

 

Otherwise I have to open a new post about how to make this device.

I seem to have jumped the gun and sent this post prematurely off in that direction!
The only data-logger I can think of is PicoScope, and I doubt there is anything that can do "off load" current whilst ignoring "on load" current. Others may prove me wrong. . . .

 

Don't worry, I know what i'm asking is not simple.

 

Don't worry, I know what i'm asking is not simple.

Need a lot more detail. 40 channels seems a bit much for a measurement system of that type.

It would be nice to have some sort of system diagram like this.
https://forum.allaboutcircuits.com/...c-controlled-battery-array.32879/post-1488959

 

I'm sorry but at the moment I can't do it. I need to do something easy to monitor no load current for automotive application. Sometime I have a car who absorb current when the car is off. I think to monitor the absorb of each fuse in order to know what is causing the battery down. Sorry for my English.

 

I'm sorry but at the moment I can't do it. I need to do something easy to monitor no load current for automotive application. Sometime I have a car who absorb current when the car is off. I think to monitor the absorb of each fuse in order to know what is causing the battery down. Sorry for my English.

Parasitic Draw Testing?

 

Not an easy task. You're measuring current at the fuse block(s), and they aren't necessarily all fed from the same source. Normal operating current may be into the 10s of amps, but just a parasitic draw of a few hundred mA can be enough to cause problems. Hall Effect current sensors like the ACS712 or ACS725 are isolated, but not very sensitive, and 40 channels worth will cost a bit, so you might want to settle for fewer, or test groups first and narrow it down. Add a bunch of analog input modules (like ADS1115) to an Arduino to read those current sensors, then log the results or something.