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What are the pros and cons of Current Limiting fuses versus Boric Acid fuses.<br />Where can a customer find the fuse curves for these fuses.

CURRENT LIMITING FUSES

1/2 CYCLE INTERRUPTION (FAST - LIMITS MAGNITUDE AND DURATION)
HIGHER INTERRUPTING CAPACITY THAN BORIC ACID
SILENT OPERATION
SQUARE D FUSE FOR FUSELOGIC APPLICATION
NO FILTERS OR VENTS
NO MOUNTING RESTRICTIONS
GENERATES ARC VOLTAGE TO DRIVE THE CURRENT TO ZERO
SILVER ELEMENT IN SAND - NO BY-PRODUCTS
BETTER COORDINATION WITH OTHER DEVICES
MAXIMUM SHORT- CIRCUIT RATING (LIMIT LET THRU CURRENT)
ECONOMICAL
SYSTEM DAMAGE PROPORTIONAL TO I2T - LIMITS DAMAGE

BORIC ACID FUSES

REFILLABLE FUSE ELEMENT (LINK) LOW COST REFILL UNIT
UTILITIES TEND TO USE TO BETTER COORDINATE WITH UPSTREAM DEVICES
THE TIME CURRENT CHARACTERISTICS SOMETIMES ALLOW BETTER PROTECTION FOR TRANSFORMERS
AT 15KV FUSES ARE AVAILABLE UP TO 720E (HIGHER THAN CURRENT LIMITING)
AT 5 KV RATINGS UP TO 1500E
NOISY AND EXHAUST INSIDE EQUIPMENT
ONLY USED IN US, CANADA AND MEXICO
DOES NOT LIMIT EQUIPMENT DAMAGE AS WELL AS CURRENT LIMITING
ARCING ROD DRAWN THRU CYLINDER
ARC DECOMPOSES BORIC ACID INTO WATER AND BORIC ACID ANHYDRIDE
MOUNTING RESTRICTIONS - CANNOT INVERT PLUS EXHAUST MATERIAL

SQUARE D OFFERS BOTH TECHNOLOGIES IN NON-DISCONNECT AND DISCONNECT STYLES

Where to find Fuse curves:

Square D DIN/E order CD from lit. center
Type 55GD/GF; 175 GD/GX/; 155GX 0110TC9601R3/01 (Characteristic Tripping Curves)


Square D DIN/E Contact Medium Voltage TAG Group 615-459-8456
25.8- 38kV

Bussmann Type MV055 http://www.bussmann.com/library/bifs/6700.pdf


Bussman Type MV155 http://www.bussmann.com/library/bifs/6701.pdf


Cutler-Hammer http://www.ch.cutlerhammer.com/unsecure/cms1/TD20A01TE.PDF
(Westinghouse RBA)

GE fuses Type EJ; EJO http://www.geindustrial.com/cwc/products?famid=15


S&C Type SM fuses http://www.sandc.com/products/sm_od/sm_od.asp


Ferraz Shawmut fuses (Gould) http://www.ferrazshawmut.com/products/mediumvolt.html.
Type A055/A155






CTA-ID : 2011505
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