Absolute max current on PR38-5_10A?

Hardware
1

What is the absolute maximum current the PR38-5_10A can handle?

I have a PR38-5_10A , the 10A variant, deployed and working well however the load is higher than I expected so I’m regularly logging 12A. I read that the boards have “about 25%” headroom for measurement, but I am already very close to 12.5A and I don’t want an errant motor start to fry the micro.

My guess is that the difference between the 10, 20, 30, 50, 100A variants is just the resistor values but my board is not easily accessible to check them. I could add or change a resistor to reduce the voltage but I’d want to go on site with a plan for what to do.

2

Hi,
The resistor is a surface mount part and not easy to replace.

If you want you can send it back and we can build a 20A version for you.

Thanks

3

As a last resort I could send it back, but it’s happily collecting data at the moment and the whole reason I got it was to help diagnose some acute issues (and its doing a very good job!).

47%20AM
Screen Shot 2020-07-12 at 9.06.47 AM.png1540×608 57 KB

If I remember right the ADC on the ATMega32U4 tolerates up to Vcc… what is the value of the burden resistor on the 10A board? If the absolute max before damaging the ADC is closer to 15A I might just leave it in for now.

4

@Bhaskar I just ordered a 50A version to see if the resolution is such that we can use the same board for all of our applications.

If so I will swap it with the 10A and then send the 10A board in for exchange. Is there an RMA process?

Thank you.

6

Hi,

This forum is really more for technical support. I would recommend creating a ticket here to get info on the status of your shipment:
https://ncd.io/order-assistance/
Someone from our shipping department will be happy to help.

Thank you,
Travis Elliott