UL-60947-7-3:2017 pdf free download – STANDARD FOR SAFETY Low-Voltage Switchgear and Controlgear一Part 7 -3: Ancillary Equipment一Safety Requirements for Fuse Terminal Blocks.
8.3.5 Mechanical strength of the connection between the terminal block base and the fuse-carrier
8.3.5DV D2 Deletion:
Subclause 8.3.5 does not apply.
8.3.5.1 Torque test on screw-type fuse-carriers
The fuse-carrier equipped with the maximum gauge no. 1 or no. 4, in accordance with table A.1, shall be screwed in five times into the terminal block base by applying the respective torque specified in table 1.
The fuse-carrier shall be securely kept in the terminal block base during and after the test, and shall show no changes impairing its normal use.
8.3.5.2 Pull-out test on screw-type and bayonet-type fuse-carriers
The fuse-carrier equipped with the maximum gauge no. 1 or no. 4, according to table A.1, shall be inserted in the terminal block base.
Screw-type fuse-carriers shall be tightened with a torque of two-thirds of the value specified in table 1. The fuse-carrier shall then be subjected to an axial pulling force as specified in table 1 for 1 mm.
The fuse-carrier shall be securely kept in the terminal block base during and after the test, and shall show no changes impairing its normal use.
8.3.5.3 Actuating forces on plug-on type or hinged-type fuse-carriers
The fuse-carrier, together with the maximum gauge no. 1 or no. 4 according to table A.1, shall be inserted in and withdrawn from or slewed out of the terminal block base.
The actuating forces shall be measured with appropriate measuring means. This test shall be conducted 10 times.
The value of each individual measurement shall be within the limit values as stated by the manufacturer.
The fuse-carrier shall be securely kept in the terminal block base during and after the test, and shall show no change impairing its normal use.
8.3.6DV D2 Addition:
8.3.6DV.1 Tab pull test
Subclause 8.3.3.6DV.1 of Annex DVA, Item A applies.
8.3.7DV D2 Addition:
8.3.7DV.1 Solid wire tightening test
Subclause 8.3.3.6DV.2 of Annex DVA, Item A applies.
8.4 Verification of electrical characteristics
8.4.1 General
The verification of electrical characteristics includes me tollowing:
— dielectric test (8.4.3);
— contact resistance (8.4.4);
— temperature-rise test of the clamping units (8.4.5);
— ageing test for screwless-type fuse terminal blocks (8.4.7).
8.4.1 DV D2 Modification by adding the following dashed items to the list:
— verification of clearances and creepage distances (8.4.2DV)
— temperature-rise for screw-less and insulation displacement terminal blocks (8.4.8DV)
— ageing test for insulation displacement terminal blocks (8.4.9DV)
8.4.2 Void
8.4.2DV D2 Modification by adding the title Verification of clearances and creepage distances” and replacing this subclause with the following:
Subclause 8.4.2 of Annex DVA, Item A applies.
8.4.3 Dielectric test
8.4.3DV D2 Modification by replacing with the following:
Subclause 8.4.3 of Annex DVA, Item A applies.