Need to monitor voltage on 48v-65v DC system with a microcontroller

To roll your own, go to

You could also look around the surplus market (I'm assuming this is a home/hobby project) and see what you can find. Some that come close are:

B.G. Micro has one: PWR1127 (have to download the catalog PDF) for only about $10. Get two!

I think 64V it just too a bit high for the circuit to be classed as SELV (Safety Extra Low Voltage). I can't remember the exact limit (43V?) but this might mean you need to include something like an opto isolator and careful PCB and enclosure design to prevent a fault causing a shock hazard to the user.

Do you want the micro to measure the 48-64V rail? In which case it might be worth using an opto anyway to prevent anything like a nearby lightening strike getting into the micro via any long wires - although there are other ways to do that. Best convert the 48-64V signal into a digital signal (example a varying frequency square wave) then put it through the opto. Best not to try putting analog signals through an opto isolator. It can be done but using a digital signal is usually easier and more accurate.

Aha... nice idea.. I hadn't thought about the VtoFreq conversion.

But still, I need to get the 64V to 5V to power all of this.. Any ideas there?

- jim

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----

----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Actually, I just realized another BIG advantage of this.. Given that the battery bank is 4 12V batteries in series, using this VtoHz idea would make it easy to measure each battery independently, which makes it easier to spot a battery with a bad cell...

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----

----= East and West-Coast Server Farms - Total Privacy via Encryption =----

See this reply > Any suggestions for voltage regulation from 60Vdc to 5Vdc, LOW current

maxim max5035 should be ok regulate max 76v input to fixed 5v output max 1A