How do you perform a primary injection test?

The Primary Injection Test Set under HV Hipot Electric Co., Ltd. can help many power workers conduct various power tests more conveniently.

Core Principle: High Voltage Hazard! Must be performed by certified professionals in a de-energized environment, strictly following safety rules.

1. Safety Prep (Most Critical!)

Complete De-Energization & Isolation: Ensure the equipment under test (EUT) and associated circuits are completely de-energized. Open all power series resonances and apply Lockout-Tagout (LOTO).

Verify, Discharge, Ground: Verify absence of voltage, discharge any stored energy, install three-phase short-circuiting grounding leads at both ends of the work zone.

Set Up Exclusion Zone: Use barriers and “High Voltage Danger” signs.

Personal Protective Equipment (PPE): Insulating gloves/boots, safety glasses/face shield, arc-flash suit.

CT Secondary Handling: Current Transformer (CT) secondary windings MUST be reliably short-circuited and grounded!

2. Connections
Securely connect the high-current generator’s output to the EUT’s primary circuit (e.g., in series with the CT primary).
Connect a reference (precision) ammeter to accurately monitor primary current.
Connect a relay test set to monitor secondary current/relay operation.
Double-check all connections: Ensure correctness, tightness, and CT secondary shorting/grounding.

3. Test Execution
Clear Communication: Assign roles (Operator, Meter Reader, Safety Watch) and signals.
Zero Start: Set generator output to zero before energizing.
Increase Current Slowly & Steadily:
Operator increases output current slowly.
Constant Vigilant Monitoring:
Reference Ammeter (Primary Current)
Relay Test Set (Secondary Current, Relay Pickup/Dropout, Timing)
Connection Points (Overheating, Arcing Sounds/Smell, Smoke)
Record Data: Stabilize current at test points (e.g., pickup value), record primary/secondary current, timing, etc.
Stop Immediately on ANY Anomaly: Any abnormality (overheating, sound, smell, meter error) requires immediate ramp-down to zero and power off!

4. Test Completion
Decrease current slowly & steadily back to zero.
Disconnect generator power series resonance.
Discharge: Discharge generator and test leads if required (per manual).
Verify De-Energized: Confirm test points are dead.
Disconnection Order: Remove test set leads first

Remove generator output leads last.
Secure Site, maintain safety grounds until work permit closure.

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By hvhipot