Requirement:
Each electronics carrier interface (144 total) will include provisions for the following 5 monitors: 2 temperatures on ladders (thermistors), 1 summed voltage on carrier (voltage across resistor chain), 1 SDD high voltage (to be determined), and 1 displacement on ladder (to be determined). The cabling for 3 of these monitors (all but 1 temperature) will be part of the readout electronics --- carrier interface cable. The other temperature monitor will be routed with the calibration/high voltage cables to the readout electronics.
Justification:
The SDD drift times depend upon temperature, and
temperature gradients on the SDDs cause nonlinearities
for drift time versus position. Physical positions and dimensions
are dependent upon temperature. Alignment and position of physical
components of the SVT must
be monitored at all times.
The sensitivity required is that change that corresponds to a
10 
m contribution to the SVT position determination.
Voltages on the Hybrid side of the carrier interface should be
monitored. Voltages and temperature should be monitored on the
readout electronics.