Hi, in the AM16/32B documentation it reads "The AM16/32B is not designed to multiplex power. Its intended function is to switch low-level
analog signals. Switched currents in excess of 30 mA will degrade the relay contacts involved,
rendering that channel unsuitable for further low-level analog measurement."
so I am assuming a 20mA maximum is within tolerance. Basically I am looking for a solution for multiple different 4-20mA sensors off a cr6 and would appreciate any other setup options that would work.
My crbasic code is using CurrentSE to read a single 4-20mA signal off of RG:
Sub Read_HPT
' 'HPT 1 RG port
' SW12 (1,1)
' Delay (1,5,Sec)
' For Count = 1 To NumToAvgReps Step 1
' CurrentSE (NumToAvg(Count),1,mV200,RG,True,3500,60,1.0,0)
' Next Count
' AvgSpa (HPT_mV,NumToAvgReps,NumToAvg())
'
' SW12 (1,0)
I suggest you use a precision resistor on each differential channel of the multiplexer. One resistor for each probe. Accuracy and temperature stability adapted to your measurement needs. Often 0.1% and 5 ..... 15 PPM