KAGRA Logbook

Reports 1-1 of 1

VIS (IX)

ryutaro.takahashi - 20:27 Wednesday 29 September 2021 (18398)

Replacement of LVDT driver for IP

[Takahashi, Sato]

We replaced the LVDT driver for IP.

We replaced the LVDT card for IP H1, H2, H3 and F0 to the modified card.
Adjusted the demodulation phase and the gain in the card.
Calibrated the F0 LVDT. Upper direction is +.
Caliblated the IP H1-H3 LVDTs. CCW direction is +.
New conversion factors are as follows.

	F0	IP H1	IP H2	IP H3
[um/count]	0.497	0.211	-0.154	0.234

Images attached to this report

Comments to this report:

masahide.tamaki - 14:00 Thursday 30 September 2021 (18406)

I changed the gain of LVDT driver for IP according to Takahashi-san's report.
Then I accepted the SDF.

Images attached to this comment

18406_1632978042_Screenshot from 2021-09-30 13-41-19.png

masahide.tamaki - 0:15 Friday 01 October 2021 (18412)

[Ushiba-san, Tamaki]

We measured tranfer function with new conversion factors and compare them with the data of Sep. 17.

The result is shown in Fig1 (IP_BLEND_LVDTY_IN1_DQ / IP_TEST_L_EXC) and Fig2 (P_BLEND_LVDTY_IN1_DQ / IP_TEST_T_EXC). We can tell the transfer function became lower with new conversion factors (green line) than previous value (blown) at high frequency.

Images attached to this comment