Today we connected the PT1000 thermostat on RCAV's stack to C3:PSL-GEN_DAQ16. This will be used for time constant between chamber to cavity measurement.
We want to learn the time constant between the chamber's outside surface to the cavity, so we need to know the temperature of these two points.
The temperature on the outside surface of the chamber can be measured by 4 sensors that we already have. For the inside,
Frank left one PT1000 on the top seismic stack, just under the cavity inside the chamber. It's wired to the D-sub connector. We made a circuit, as shown below, to measure the change of the resistance( which is proportional to T) of the sensor.
insert fig

R(T) at 30 C is about 1.2 k ohms.
SR560 is set to DC couple, gain x2. The output is connected to C3:PSL-GEN_DAQ16
This should give us the temperature of the stack inside the vacuum.
Now I'm waiting to see any change of the voltage.
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