UL 2748-2017 pdf download

UL 2748-2017 pdf download.Arcing Fault Quenching Equipment.
16 Power-Frequency Withstand Voltage Tests
16.1 Low-voltage quenching devices shall comply with the power-frequency withstand voltage tests of Metal-Enclosed Low-Voltage AC Power Circuit Breaker Switchgear Assemblies — Conformance Test
Procedures, ANSI/NEMA C37.51.
162 Medium-voltage quenching devices shall comply with the power-frequency withstand voltage tests of Metal-Enclosed Interrupter Switchgear Assemblies — Conformance Testing. ANSI/NEMA C37.57.
17 Maximum Withstand Current Test
17.1 Quenching devices shall be subjected to a maximum withstand current test to demonstrate the ability of the quenching device, including the bus and connections, to carry current equal to the maximum arcing fault current rating assigned to the device for the rating short-time withstand duration.
17.2 The test method for low-voltage quenching devices shall be similar to the Short-Time Withstand
Current Test method described in Metal-Enclosed Low-Voltage AC Power Circuit Breaker Switchgear
Assemblies — Conformance Test Procedures, ANSI/NEMA C37.51, wTth the following molications:
a) The available short-time withstand current shall be calibrated at the line terminals of the equipment in which the quenching device is installed dunng the test. Calibration of the test circuit shall demonstrate the circuit is capable 01 delivering the rated maximum withstand current for the entire rated short-time withstand current duration of the quenching device.
b) The short-time withstand current is to be initiated by action of the quenching device Alternatively, the test may be conducted using a previously triggered quenching device, by closing the test station switching device onto the circuit. The current is to be maintained for no less than the rated short-time withstand current duration of the quenching device. The actual current through the quenching device is to be measured during the duration of the test. The actual current delivered to the test point will be reduced by the Impedance of the arc and the test sample
C) Tests shall be conducted with a three phase source of supply. Testing with a single phase source of supply is not representative of three phase testing.
d) The quenching device shall carry the test current for the entire duration of the test. Interruption of the test Current prior to rated short-time withstand current duration shall be considered an unacceptable result.
e) The contacts of the quenching device may be welded in the closed position at the conclusion of the test. Quenching devices complying with 13.4 are not required to be functional at the conclusion of the test.
f) All local and remote indication means provided shalt indicate that the arc quenching function has operated, and shall not reset automatically.
9) Quenching devices that are intended to be reset, rather than repaired or replaced, after a quenching operation shall meet the required electrical creepage and clearance distances of Section 11 after the device has been reset tollowing the short-time withstand test. Quenching devices that require repair or replacement after a quenching operation are not required to meet the required creepage and clearances at the conclusion of the short-time withstand test.
18 Internal Arcing Fault Test
18.1 The purpose of this test s to demonstrate the quenching dev,ce does not create an arc fault hazard during the quenching operation. ibe quenching device shall be installed in complete equipment in accordance with the manufacturer’s Installation instruchons, or may be tested as an open device without an enclosure. The equipment shall be subjected to testing in accordance with the Guide for Testing Metal-Enclosed Swttctigear Rated Up to 38 kV for Internal Arcing Faults. IEEE C37.20.7.
18.2 When tested in complete equipment, indicators shall be provided around the vertical section of the equipment containing the quenching device. Indicator placement shall be in accordance with the requirements of the Guide for Testing Metal-Enclosed Switchgear Rated Up to 38 kV for lntemal Arcing Faults, IEEE C37.20.7 for the accessibility type ol the equipment containing the arc quenching device. When tested as an open device, indicators shall be placed around the entire quenching device in a similar manner, at a distance of 4 inches from each surface of the quenching device.