Last week, we changed the power supply for the FCIM crate to an independent power supply (see entry 51645)

It didn’t help to solve the jump issue and we found that the coil current monitor channels  became very noisy for marionette vertical coils and mirror coils (pic1). This situation never appeared in the past. So we changed the power supply back to it original one, and the excess of noise disappeared.  

Then we tried to recover the system, starting from the control of the bench but we found that the DDS board was not working anymore. To confirm the problem is the DDS board and not the crate, we plugged the FCIM DDS module to the SQB2 crate, there was still no output signals. So at this moment we are providing the 10kHz signal for LVDT with an external signal generator. (Pic2) Under this condition, we checked again the coil current monitor signals, the jumps still exist (pic3).  We are still suspecting that the electric problems are coming from the crate. A spare crate has been sent from Nikhef this Monday, we expect it to arrive before Friday.