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#16741 - 11/15/02 09:46 PM cartridge fuses
mike knight Offline
Junior Member
Registered: 10/11/02
Posts: 5
how do you size a cartridge fuse to fit a particular disconnect? in the switchgear i need fuses it says only "type j" but i'm not sure how to order them so they fit right.
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#16742 - 11/16/02 03:43 AM Re: cartridge fuses
sparky Offline
Registered: 10/18/00
Posts: 5303
if your disco states type j, then you only need spec voltage & amperage...
#16743 - 11/16/02 08:52 AM Re: cartridge fuses
mj Offline
Registered: 06/10/02
Posts: 186
Loc: meriidian, ms
a listed disconnect will indicate the size, type ocpd required.
#16744 - 11/16/02 07:27 PM Re: cartridge fuses
Bjarney Offline
Registered: 04/10/02
Posts: 2527
Loc: West-Southern Inner-Northeast ...
An example is

Their Class-J versions [LPJ-series] up to 600A @ 600V and 300,000AIC.

[This message has been edited by Bjarney (edited 11-16-2002).]
#16745 - 11/16/02 08:08 PM Re: cartridge fuses
harold endean Offline
Registered: 02/16/02
Posts: 2233
Loc: Boonton, NJ
Just make sure you follow what the blue print says. You might fail a final inspection if the print calls for a type "J" fuse and you have a type "R" fuse instead.
#16746 - 11/16/02 08:26 PM Re: cartridge fuses
Trumpy Offline

Registered: 07/05/02
Posts: 8211
Loc: SI,New Zealand
What is a j-type fuse?.
We work on the following type fuses,(HRC)
to IEC Requirements:
P1: Semi-conductor Devices Protection- 1.0-
1.1 protection.
Q1: General protection, lighting power.
Q2: General protection Sub-Mains, other Equipment.
R: Motor rated links for 3 Phase or other motors upon start-up.
Let's face it, these days if you're not young, you're old - Red Green grin
#16747 - 11/17/02 07:51 AM Re: cartridge fuses
Bjarney Offline
Registered: 04/10/02
Posts: 2527
Loc: West-Southern Inner-Northeast ...
Trumpy—in general, 600V Class-J fuses are available in "semi-fast" [non-motor]and "slow" time-current curves [motor]. About 10 years ago the interrupting rating of 300KA became available in the US. At that time the justification was that there were a ±dozen US cities with "downtown" electric networks that were so stiff that 200kA interrupting was underrated.

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