LIGO Document E1400115-v1

L1 SUS HLTS SR3 Acceptance Document

Document #:
Document type:
E - Engineering documents
Other Versions:
L1 SUS HLTS SR3 Acceptance Document

For General Acceptance Documentation common for all HLTS refer to aLIGO SUS HLTS Acceptance Documentation.

Calum Torrie signed March 26th 2014. Punch-list items listed below. All closed and accounted for else punch-list.

Punch list items -
i) Need excel spreadsheet with input data from build.
ii) Refer Bug 733 for cross coupling issue highlighted below. No fix.
iii) Magnet missing from SR3. Refer to bug 175. No fix planned for now.

Punchlist items and their resolution will be tracked in T1400181. They will not be updated on this Acceptance Document filecard.

Files in Document:
Notes and Changes:
I. Committee (* indicates review chair)
Rich Abbott, Alastair Heptonstall, Calum Torrie*, Jeff Lewis, Fabrice Matichard, Celine Ramet.

II. Documents for Review (against list from M1100282)
Top Assembly Name: AdvLIGO SUS HAM5-L1, XYZ Local CS for HLTS (SR3)

ICS Assembly #:
- ICS Assembly Load:

Acceptance document:
This filecard serves as the acceptance document for L1-SR3.
For common material for all HLTS suspensions, see

ICS inventory

The electronics for L1 SUS SR3 can be found in the racks

Test results:
- Calibrated, M1toM1 Transfer Functions (DAMPING OFF):

A ~2.05 Hz pitch mode to vertical DOF cross-coupling present, see - no fix planned, just monitored.

- Calibrated, M1toM1 Transfer Functions (DAMPING ON):

- Calibrated, M2toM2 Transfer Functions (DAMPING ON/OFF):

- Calibrated, M3toM3 Transfer Functions (DAMPING ON/OFF):

Discrepancy with PR3 due to missing SR3 LL magnet, see: - no fix planned for now.

- Calibrated, M2toM3 Transfer Functions (DAMPING ON/OFF):

Verifying that the high frequency turn-up is sensor (and not actuator) read-back related and only associated with a single channel on the M2 stage.

- Calibrated OSEM Sensor ASDs, All Stages (DAMPING ON/OFF):

- B&K Hammer Cage Resonance Transfer Functions:

- Coil Driver Noise:
- Coil Driver Response in all states:
Noise measurements presented are for MC2, however, SR3 uses the same coil drivers and we would therefore expect identical performance.

- Violin Mode Frequencies and Q
Measured violin modes:
- Summary of modeled violin modes:
Measured violin mode Qs are used to estimate wire losses (structural and thermo-elastic) and hence expected thermal noise at lower frequencies. Additional data will be taken and subsequent analysis is still to come, but this falls outside of the scope of the fabrication acceptance review.
Note added 5th Sept 2014 for clarification (NAR/CIT)
Predicted violin mode frequencies and Qs for all types of suspensions are given in T1300876. These can be compared to measured values.
Measuring Qs is not a requirement for SUS acceptance.
For Installation acceptance it has been agreed that we should measure Qs once for each major suspension type.
For HLTS we measured Qs on L1 PR3. see
Measured Qs are all higher than the model predictions.

Channel/Signal List and Calibrations
For latest measurements of OSEM Sensor's Open Light Current, See
Otherwise calibrations are assumed to be as shown in HLTS Control Design Description, with a roughly 20% uncertainty

III. General notes and action items:
- The review team should review E1201041 in detail - unless the SUS Acceptance format changes and E1201041 is no longer the preferred method of presenting this info.

Referenced by:

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