Routine Test Items And Test Standards For Switch Cabinets

Routine Test Items for Switchgear Cabinets
Routine Test Items
Insulation Resistance Measurement
Main Circuit Resistance Measurement
AC Withstand Voltage Test
Action Characteristics and Operation Mechanism Inspection and Testing
Insulation Resistance of Control, Measurement and Other Secondary Circuits
Reverse Trip, Five-Prevention Device Inspection
Ground Resistance Test
General Test Cycle
Extraordinarily Important Equipment: 6 years; Important Equipment: 10 years; General Equipment: As Required.
Test Requirements and Instructions
Insulation Resistance Measurement Requirements
1) The insulation resistance of the switch body at 20℃ should be no less than 300 MΩ;
2) The primary insulation resistance of metal oxide surge arresters, PT, and CT should be no less than 1000 MΩ at 20℃, and the secondary insulation resistance should be no less than 10 MΩ.
Note: The primary resistance is measured with a 2500V megohmmeter, and the secondary resistance is measured with a 1000V megohmmeter.
Main Circuit Resistance Measurement Requirements
≤ 1.5 times the manufacturer's specified value (attention value).
Note: The measurement current should be greater than 100A.
AC Withstand Voltage Test Requirements
1) The test voltage value for circuit breakers should be in accordance with DL/T 593 regulations.
2) The primary winding test voltage value of CT and PT (fully insulated) should be 85% of the factory value, or 30kV if the factory value is unknown.
3) When circuit breakers, CT, and PT are tested together, the lowest test voltage should be applied.
Note: The test voltage application method: relative to ground and between phases during closing; at opening, at each contact.
High Voltage Switch Dynamic Characteristics Tester
Requirements for Action Characteristics and Operation Mechanism Inspection and Testing
1) The switch should reliably operate within the rated voltage range of 85% to 110% when closing, and reliably operate within the rated voltage range of 65% to 110% when opening (for DC), when the voltage is lower than 30% of the rated voltage, the trip device should not trip.
2) Detection of the working current of the energy storage motor and the energy storage time, the detection results should comply with the requirements of the equipment technical documents. The motor should be able to operate reliably under 85% to 110% of the rated current.
3) The DC resistance result should comply with the requirements of the equipment technical documents or the initial value difference should not exceed ±5%;
4) The opening and closing time, speed, synchronization, and bounce of the switch should comply with the requirements of the equipment technical documents.
Note: The test voltage application method: relative to ground and between phases during closing; at opening, at each contact.
Requirements for Control, Measurement and Other Secondary Circuit Insulation Resistance
Insulation Resistance should generally be no less than 2 MΩ;
Note: Measured with a 1000V megohmmeter.
Requirements for Inspection and Testing of Reverse Trip, Five-Prevention Device
Comply with the equipment technical documents and five-prevention requirements.
Requirements for Ground Resistance Test
Cycle: 4 years
Requirements for Ground Resistance Test: no more than 4 Ω.