• Topic ID: id_16157760
  • Version: 2.0
  • Date: Jun 10, 2020 2:46:39 AM

Meter Verification (Pro, RT, VCT)

Prerequisites

Overview

Objective: Verify that the internal kV and mA meters are functional. If the meters are not functional, the inverter cannot be used in the system. Summary:

  • Connect meter to test points

  • Launch tool

  • Take measurements and enter results

Procedure

  1. Remove gantry right side cover if it's not already removed.
  2. Turn off all three service switches on the Service Switch Panel (AXIAL DRIVE ENABLE, HVDC ENABLE, 120VAC).
  3. Rotate the gantry such that HP inverter assembly is in the 2 O'clock position.
  4. Remove the inverter cover nearest the cradle.
  5. Attach a protective ESD wrist strap.
    6. Notice Image
    • notice
    • Failure to use protective ESD equipment may result in destroyed/damaged equipment.
  6. Remove jumper TP 17.
  7. Using a digital multi-meter (DMM / DVM) as a dc ammeter, connect the red signal lead to TP 19 and the black common lead to TP 15.
  8. Restore the 120VAC power and press DRIVES_RESET on the service switch panel.
  9. Launch the GENERATOR TOOL from the Service Desktop. For more details, see JEDI Generator Tool.
  10. Wait for gantry display to reset. No flashing lights on the gantry display indicate this.
  11. Launch the METER VERIFICATION tool.
  12. Verify mA meter:
    1. Using the tool, enter a delay time to allow you to walk to the meter.
    2. Run the test and walk to the meter.
    3. Record the ending mA reading on the multi-meter, to one decimal place. If this accuracy cannot be obtained, change range on meter and redo test.
    4. Enter the value in the box for mA Low Scale. It will appear in the mA High Scale box automatically. The difference between the two measurements should appear in the delta column.
    5. Verify that the delta is within the limits (on the right).
    6. Remove the DVM leads from TP 15 and TP19. Reconnect jumper.
  13. Verify kV meter:
    1. Switch multi-meter to DC volt meter.
    2. Using the digital multi-meter (DVM) as a dc voltmeter, connect the red signal lead to KV_N (TP6) and the black common lead to KV_GND (TP8).
    3. Run the test again and walk to meter.
    4. Record the ending voltage on meter to one decimal place. If this accuracy cannot be obtained, change range on meter and redo test.
    5. Multiply by 10.
    6. Enter this calculation in the box for kV.
    7. Verify that all three deltas are within the limits.
      note:

      kV may not have a limit. The system will save the data.

Finalization

  1. All three measurements should be within the limits.
  2. Replace inverter if necessary.
  3. Record the results on the HHS data sheet.