- Topic ID: id_26983480
- Version: 2.0
- Date: Jan 25, 2021 12:48:25 AM
TGPG Replacement
Prerequisites
Overview
This procedure defines the steps necessary to replace the TGPG board.
1 Removing The TGPG
Procedure
- Remove the gantry right side cover.
- notice
- Turn off all three (3) switches (Axial Drive, HVDC, and 120VAC) on the Service Switch Panel.
- Perform all required LOTO activities.note: Front and rear access is required for this procedure.
- Remove gantry left side cover. If further access is required,
remove top and rear covers.
Refer to
- Remove the 8 thumbscrews in the TGPG cover, then remove the cover.
- Disconnect all cabling into the TGPG.note: If the cables are not labeled, label them as they are removed.
- Remove the cabling assembly plate.
Figure 1. TGPG

- Remove the ten screws attaching the TGPG board.
- Remove the defective TGPG.
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2 Install TGPG
Procedure
- Put the new TGPG board in place.
- Secure the board by replacing the ten screws.
- Install the cable assembly plate.
- Carefully install all of the removed cables, making sure that no pins are bent during engagement.
- Remove LOTO, and power up everything except the gantry.
- Before powering ON the 120 VAC gantry power, open a shell (terminal)
window on the console and type the following
cd /usr/g/fw ENTER
touch tgpFtp ENTER
note: These commands must be performed to assure that the FLASH download procedure successfully downloads the TGPG firmware from the OC, regardless of the status of the TGPG programming. - Turn ON all three (3) switches (Axial Drive, HVDC, and 120VAC) on the Service Switch Panel and press the E-stop reset.
- Execute Flash download query and update. Refer to the Flash download procedure if necessary.
- Perform the power supply adjustment procedure in the Finalization
section of the TGPG Power Supply Replacement.note: You will have to remove the M6 top and bottom mount screws holding the power supply in place using a 5 mm hex wrench as noted at the beginning of the power supply replacement procedure to have access to the adjustment screws.
- Turn off the Axial Drive, HVDC and 120 VAC service switches.
- Replace the TGPG cover.
- Replace gantry covers except for the right side cover that allows access to Service Switch Panel.
- Turn on the 120 VAC, HVDC and Axial Drive service switches.
- Replace gantry right side access cover.
3 Finalization
Procedure
- Perform the System Scanning Test from the Functional Checks folder.
