UL 248-7-2019 pdf free download

UL 248-7-2019 pdf free download.LoW-Voltage Fuses – Part 7 : Class H Renewable Fuses.
This UL 248-7 applies to Class H Renewable fuses rated 600 A or less and either 250 or 600 V ac. DC ratings are optional.
4 Classification
Class H Renewable fuses have an interrupting rating of 10,000 A. Each of the voltage ratings. 250 V ac and 600 V ac. is divided into six body sizes with the maximum current rating, I, for each size as specified in this Part. These fuses are not classified as current limiting. Time-delay ratings are optional.
These fuses may be restored to service after operation by the replacement of the renewal element with one recommended by the manufacturer.
5 Characteristics
5.2 Voltage rating
For AC. the rating shall be 250 or 600 V ac in accordance with dimensions shown in Figure A and Fg.ire B. The DC voltage rating may be different from the AC rating.
5.3 Current rating
Refer to Figure A and FiQure B for range of current ratings in each body size for each vo’tage rating.
5.5 InterruptIng rating
For AC— 10,000 A
For DC-10.000A
6 Marking
6.1 Marking of fuses
In addition to the requirements in Part 1: The fuse shall be marked Renewabl& and with the recommended renewal element.
Each renewal element shall be marked in accordance with Part 1. Clause 6.1, Items a. b. and c.
g) The fuse shall not be marked Current Limiting.
8.2 Verification of temperature rise and current-carrying capacity
8.2.3 Test method
1.0 I, — Temperature rise
1.1 I,, — Current-carrying capacity. I,
8.2.3.1 Fuses rated 600 A or less
In add ition to the requirements in Part 1: At the conclusion of the temperature rise test, the test current shaH be increased without interruption to 1.1 l for a period of not less than 15 mm for fuses rated 0 — 200 A and not less than 30 mm for fuses rated 201 — 600 A. Temperature is not to be monitored duflng this time.
8.2.4 AcceptabilIty of test results
In addition to the requirements in Part 1: The maximum temperature rise shall not exceed the following:
Body – 80C
Contacts –
S100A— 55C
>100A—75°C.UL 248-7-2019 pdf free download.