wp 5305 RichardM HughR

The HEPI Pump Servos have forever been powered by bench test power supplies and these should be available for that purpose and they are expensive for use in a permanent setup.  Additionally at EndX, the pressure sensors have been excessively noisy since 26 Feb, relative to the other locations and we've suspected the power supply.  So Richard procured/built a supply for permanent install.  We swapped it over but there was no improvement on the noise of the pressure sensors.

We tried a number of additional things.  Disconnect grounds of the power supply; disconnect pressure sensors, power down the VFD of the motor Controller.  No real changes.  If you compare the pressures on the three servos at LHO, the EndX is way noisier so we know it can be better.  Richard has some suspicion of the Servo itself now.