• SIGNA™ Hero 3.0T Service Methods
  • 5852800-8EN Revision 1.0
  • Object ID: 00000018WIA30CCFE20GYZ
  • Topic ID: id_13105925 Version: 3.3
  • Date: Jul 13, 2021 6:28:47 PM

Ground Leakage Current Test

Prerequisites

Table 1. Personnel requirements
Required personsPreliminary requirementsProcedureFinalization
2Not Applicable minutes180 minutes5 minutes
Table 2. Tools and test equipment
ItemQuantityEffectivityPart numberManufacturer
Dale 600 or 601 (120 VAC) or Dale 600E or 601E (220 VAC) Safety Analyzer1-

600/601: 46-285647P1 or 46-328406G1; 600E/601E: 46-285647P14 or 46-328406G2

-
Fluke ESA612 Electrical Safety Analyzer1-

5453348-2 (220v)

-
Hazard Class 2 Personal Protective Equipment (PPE)2-

-
Digital Volt Meter (DVM) with Jumper Leads1-

46-194427P284

-
Personal Lock2-

46-194427P320

-
Red Warning LOTO Tag2-

46-194427P322

-
Multi-Locking Device (for multiple service technicians)1-

46-194427P313

-
Table 3. Safety
Table 4. Required conditions
ConditionReferenceEffectivity

All personnel performing this procedure must have completed proper electrical hazard training courses.

--

Verify Ground Resistance Checks are completed and passed.

--

Confirm all power and ground cables are installed correctly.

--

Confirm the Main Disconnect of the PDU is ON.

--

Confirm all subsystem cabinet circuit breakers and subsystem power switches are ON.

--

Confirm Hazard Class 2 Personal Protective Equipment (PPE) is available.

--

About this task

Before performing this procedure, personnel must have completed proper electrical hazard training courses, including

  • Power and Grounding Audit (GEHC-TECH-AMOL-CM9010) or equivalent

  • Electrical Safety Authorized Course (GE-EHS-280) or equivalent

This document contains a method for measuring Ground Leakage Current using different brands of Safety Analyzers. Only one of the Safety Analyzers listed in Tools and Test Equipment is required for this procedure.

Review and understand all Required Conditions before beginning this procedure.

Topic ID: id_SL4695102-1178750

Ground Leakage Current Test

About this task

The following table highlights the tasks in the Ground Leakage Current Test procedure in the order that they should be performed. Some equipment listed are optional equipment and are only tested if on the system.

Table 5. Tasks for Ground Leakage Current Test
Task to be performed Go to section Required/Optional
Record safety analyzer data and link to form Recording Readings Required
Set up the Safety Analyzer Setting Up the Safety Analyzer Required
Perform LOTO Performing LOTO Required
Measurement Testing the System Ground Leakage Current Required
Restore the System Restoring the System Required
Finalization StepsEnd of documentRequired
Topic ID: id_SL4695104-1178750

Recording Readings

About this task

As this procedure is only performed when local regulations or codes require it, the readings gathered during this procedure must record for the local authority. A copy of the measurements should also be retained with the site documentation. Use the following tables to record your measurements. Mark any fields that are not applicable to the current location as “not applicable” or “N/A”.

Table 6. Data Sheet
Safety Analyzer Information
Brand of Safety Analyzer
Safety Analyzer Model No.
Safety Analyzer Serial No.
Calibration Date
Date of Tests
Name of Tester (Printed)
Signature of Tester
Measuring Point Max Leakage Current if < 5.0 mA, PASS
Facility Disconnect
Topic ID: id_SL4695459-1178750

Setting Up the Safety Analyzer

Procedure

  1. Two types of safety analyzers are available. Use the instructions for the safety analyzer that is available.
  2. Set up the safety analyzer near the front of the PDU.
  3. Using the Dale Safety Analyzer:
    1. Connect one clamp-type lead to the EXTERNAL jack on the top of the Dale Safety Analyzer. Connect the other clamp-type lead to the CHASSIS jack on the top of the Dale Safety Analyzer. See illustration below.
    2. On the Dale Safety Analyzer, set the main selector switch to EXTERNAL.
      Figure 1. Connections on Dale Safety Analyzer
  4. Using the Fluke ESA612 Safety Analyzer:
    1. Turn on the Fluke Safety Analyzer.
      Figure 2. Fluke ESA612 Electrical Safety Analyzer
    2. Select the [point to point] button.
    3. Select the [F3 or Leakage] button.
    4. Select the [Up Arrow] once so that AC Only displays.
    5. Insert the leads into the Input Jacks.
  5. The safety analyzer is now set up with the two leads attached and ready to be connected to the PDU.
Topic ID: id_SL4702270-1178750

Performing LOTO

Procedure

  1. Properly shutdown the system and Turn Off Main Breaker at ISC PDU.
  2. Turn Off MDP or Facility PDU breaker that supplies power to the system.
  3. Perform LOTO at the breaker of MDP or Facility PDU.
  4. At the secondarily terminal (output) of the main breaker, use a voltmeter to measure the voltage between each phase terminal and GND (ground). This reading should be <1V.
Topic ID: id_SL4702287-1178750

Testing the System Ground Leakage Current

Procedure

  1. Setup Safety Analyzer per following steps.
    1. Disconnect the ground wire from the Facility Disconnect and attach it to the EXTERNAL clamp-type lead on the Safety Analyzer.
    2. Connect the Chassis clamp-type lead on the Safety Analyzer to the Facility Disconnect Ground Bus Bar.
    Figure 3. Setup of Safety Analyzer
  2. Remove LOTO and turn on the facility Disconnect power
  3. Turn on the main power switch on the ISC PDU.
  4. Press the EMO RESET switch.
    Figure 4. Main PDU Circuit Breaker
  5. Confirm that system boot up properly.
  6. Record the ground leakage current. (See Recording Readings.)
    1. Confirm the leakage current is less than 5000 µA (5.000 mA) and record this value.
    2. If leakage current greater than 5000 µA (5.000 mA), a serious leakage current problem exists that must be corrected.
      Note: On the Dale Safety Analyzer, 500 mV corresponds to 500 µA (0.5 mA) of leakage current.
      If the leakage current is more than 5000 µA (5.000 mA)...

      Do not proceed with further testing until leakage current is less than 5000 µA (5.000 mA).

      Proceed directly to remove power at the MDP and LOTO the MDP.

      Check all system ground connections to troubleshoot and isolate source of leakage. Do not proceed with further testing until the cause for the leakage is found and fixed. As a failing ground leak current check is unusual, seek technical support from the local power and grounding expert before proceeding with any actions.

Topic ID: id_SL4702484-1178750

Restoring the System

Procedure

  1. Properly shutdown the system and Turn Off Main Breaker at ISC PDU.
  2. Turn Off MDP or Facility PDU breaker that supplies power to the system.
  3. Perform LOTO at the breaker of MDP or Facility PDU.
  4. Remove the leads from the Facility Disconnect Ground Bus Bar and the ground wire.
  5. Reconnect the ground wire to the Facility Disconnect Bus Bar and confirm a tight connection.
  6. Remove LOTO and turn on the facility Disconnect power
  7. Turn on the main power switch on the ISC PDU.
  8. Press the EMO RESET switch.
    Figure 5. Main PDU Circuit Breaker
  9. Proceed to the Finalization steps.
Topic ID: id_14962976

Finalization

Finalization

If this procedure is being performed at a time other than initial installation, run Check Scan (Good-Bye) to ensure the system is ready for patient scanning.

If this procedure is being performed as part of installation, proceed with installation instructions.