Debug RFI

The temperature control of the filter route does not work intermittently

Information about the electronics is here:

From this book we get that (thanks to Michel Crausaz):

we have

• the controller (JUMO) it seems to work
• pre amp (with test points)
• amp OPA 541M (with test points of the output and the power supply) 

You can use this kind of connectors with the voltmeter:

The JUMO regulate only if the temperature is lower than 18 degrees (the set point is 18 degrees)

The associated service is C2_jumo (meulplot) the sensor tair must be at 18 deg mini. It's not the case now.

If the temperature is over 18deg (the afternoon) normally the control voltages (3 test points, see below) must be zero 

If its lower than 18deg we must have something....

1) test the jumo: photos here: 

• Check <Jumo> then <OP02>

voltmeter 

2) test the ampli OPA 541M, photos here:

• Check all power supply
• Check <Charge-GND>

It's must be interesting to move the filter wheel during the measurement with TCS_rfi -p <n>, <n>=1..12 to see if something changes.

we have a spare for the OPA541M:

After that we continue further....

LW 28/04/2022