We took a first set of transfer functions (Local to Local) between 10Hz and 1000Hz (without baffle – No TMD – No vibration absorbers – No Viton pads under the keel masses - ITMY and FMY damped). After comparing with the measurements before the cartridge install, we can notice:

-          No extra resonance created by the HEPI Post between 10Hz and 1KHz (ST1 CPS transfer functions). Obviously, the resonances of the teststand are not visible anymore (first resonance at 19Hz).

-          First resonance of stage 1 is 217Hz (it will be damped by the vibration absorbers on the door of stage 1)

-          Second resonance observed on stage 1 at ~250 Hz (blade 0-1). The HAM-ISI TMDs retuned for BSC-ISI (E1100963-v1) will be later installed.

-          New resonances in the stage 2 transfer functions (53Hz). It is most visible in the Cartesian to Cartesian transfer functions.

The vibration absorbers were installed on the 3 doors of stage 1 (2 per doors). For the first test, masses are resting on 4 Viton pads (0.25”x0.25”x.0125”) and the lid is not added. Transfer functions show a reduction of the resonance at 214Hz by a factor of 6 in the X, Y, RX, RY. Tests with differentpads will be performed when the ISI will be available.

Reference Transfer functions (L2L) without baffle – No TMD – No vibration absorbers – No Viton under the keel masses - ITMY and FMY damped

In the local basis

seismic/BSC-ISI/H2/ITMY/Data/Figures/Transfer_Functions/Measurements/Comparison/

LHO_ISI_BSC8_Comparison_TF_L2L_ST1_ACT_H_to_ST1_CPS_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST1_ACT_V_to_ST1_CPS_V_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST1_ACT_H_to_ST1_L4C_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST1_ACT_V_to_ST1_L4C_V_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST2_ACT_H_to_ST2_CPS_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST2_ACT_V_to_ST2_CPS_V_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST2_ACT_H_to_ST2_GS13_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_L2L_ST2_ACT_V_to_ST2_GS13_V_20111206_vs_20120106.fig

In the Cartesian basis – Recomputed from Local measurements:

seismic/BSC-ISI/H2/ITMY/Data/Figures/Transfer_Functions/Measurements/Comparison/

LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_H_to_ST1_CPS_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_V_to_ST1_CPS_V_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_H_to_ST1_L4C_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_V_to_ST1_L4C_V_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST2_ACT_H_to_ST2_CPS_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST2_ACT_V_to_ST2_CPS_V_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST2_ACT_H_to_ST2_GS13_H_20111206_vs_20120106.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST2_ACT_V_to_ST2_GS13_V_20111206_vs_20120106.fig

Transfer functions L2L without baffle – No TMD – Vibration absorbers (0.25”x0.25”x0.125”) – no lid (cables touching the mass of the 2x1 vibration absorbers in corner ) – No Viton under the keel masses - ITMY and FMY damped:

seismic/BSC-ISI/H2/ITMY/Data/Figures/Transfer_Functions/Measurements/Comparison/

LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_H_to_ST1_CPS_H_20120106_vs_20120110.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_V_to_ST1_CPS_V_20120106_vs_20120110.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_H_to_ST1_L4C_H_20120106_vs_20120110.fig
LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_V_to_ST1_L4C_V_20120106_vs_20120110.fig