M400 and C125 CAN multiplier, divisor, adder set up

[71dsp]

We have an M400 and a C125 in a track car communicating via CAN. The M400 sensors are set to imperial units, and we didn’t realize that the C125 can only receive SI units. What we elected to do was to use the channel setup multiplier, divisor, and adder functions to convert the imperial messages to SI (and then the C125 displays imperial units).

For the temp sensors, something strange appears to be happening. Let’s say a temp is being sent that is 70F. I set the channel as following - multiplier 5, divisor 9, and adder -18 (can’t input 17.78), but the result is not correct. I was able to get the correct temp by using the same multiplier and divisor, but I had to set the adder to -178, which I don’t completely understand. Can anyone shed some light on this?

[David Ferguson]

The base unit is .1 degC, not 1 degC. That's why your adder has to be multiplied by 10.

[71dsp]

Excellent David! Thank you for the quick reply. I thought that was happening, but didn't want to assume.