T. Yamamoto, K. Tanaka
### Summary
## HWP
According to klog16172, we couldn't get the HWP to work remotely. Today DGS people fixed the problem and we confirmed that we can now run HWP from the remote.
## Beam shutter
In order to align IMC and watch the transmitted flash from IMC, we tried to open the beam shutter in PSL room. But we could not open it because beam shutter driver has broken due to the power outage.
So we bring it back Mozumi and ask Shimode-san to repair it. And according to klog9057, there is a spare driver somewhere, so we need to find it.
### What we did
## HWP
- Firstly, we reconnected the LAN cable to HWP with the so-called Oshino-san's technique.
- We sent the command to move the HWP and confirmed that the motor sound attached to the HWP was sounding in the PSL room.
- We also confirmed that the value of the power meter attached to the beam dump, which is hit when the beam shutter is closed, changes when the HWP is turned.(Before turning the HWP, the value was ~ 0.87 W. After turning the HWP, the value was ~ 0.3 W.)
## Beam shutter
- Now we opened the shutter to see if the beam was hitting the IMC REFL camera, but we noticed that the light was not reaching the IMC REFL table.
- As a result, it was found that the shutter was not opened even though the command to open the shutter was sent.
- At first, we noticed that the power light of the shutter driver was off, and the DC power supply for the driver was turned off. So we tried to turn on the DC power supply, but the driver power light did not come on. we also tried to send a command to open the shutter in this state, but the shutter still did not move.
- We then checked to see if the command to send the shutter could be sent. Since the shutter is turned on and off by applying a 5V (0V) voltage directly from the DAC, I plugged the DAC into an open ADC port and checked if the voltage was applied.
- we was able to confirm that there is a 5 V (0 V) output with on/off on the ADC side, so the signal must have been sent.
- Finally, we opened the driver, and with the DC power supply and DAC connected, we checked the p.3 in this document to make sure that the proper voltage was applied in the circuit.
- IN+ in the figure on p3 should have 5V applied to it, but it turns out that it does not. (Other than that, 9V was applied to V2, which should have been 9V, and 24V was applied to V1, which should have been 24V.)
- Also, right after the signal from the DAC was put into the circuit, there was already no voltage applied.
- Based on the above, we thought that the screwdriver was malfunctioning, so we brought it back to Mojyu and asked Shimode-san to investigate and repair it further.