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- Ensure the fans are plugged in and working.
- Turn on the master power button above the middle NIM rack (blue circle in Fig. 13).
- Turn on the computer.
- Turn on the NaI(Tl) detector electronics (right-hand NIM rack next to iSEG crate, the right red circle in Fig. 13), only after ensuring that the fan under it is working.
- Turn on the fast signal processing electronics (left-hand NIM rack, the left red circle in Fig. 13).
- Turn on the iSEG voltage crate power found behind the unit near the power cord.
- Launch the iSEG control software at the NGR computer (Fig. 14).
Figure 14. iSEG Hard ware Setup and Main screen. The controller cards may be the EHS or EHQ model and are labeled accordingly.
- Make sure the voltages (Vset) for ESQ00/EHS00 and EHQ01/EHS01 are set (Fig. 15). Modify the Vset fields as follows:
- Channel 0 = 0 (unused and available for spare channel)
- Channels 1 and 7 = 1100 V (plastic scintillators in the doors)
- All other channels = 1300 V (shell-shaped plastic scintillators)
- If one of the channels on the EHS/EHQ modules has failed, Channel 0 may be in use—be sure you understand which scintillators are connected to which channels, because the door and hoop PMTs require different operating voltages!
Figure
Figure 15. EHS/EHQ 00 and 01 iSEG Multi-Channel HIgh-Voltage Modules Screens; VRamp and IRamp fields are circled in red. - Make sure voltage ramp (VRamp) is 5% or lower and the current ramp (IRamp) is 50% or lower. The iSEG software does not remember these values between sessions!
- Click on the Module access menu and click Instructions for all channels > On (ctrl+o) to start ramping up the voltage.
- Wait until ramp-up completes (1–2 minutes if proper values are used).
- Exit the iSEG program.
- Answer No to the prompt when asked to ramp voltages back down. If you answered Yes inadvertently, start again at Step 8.
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