Document No.
1026-01
Howar
How d Industries, Inc.
ard
ISO-9001 Cer
ISO-9001 tified
Certified
Isolation Link
For Series Connection with Draw-Out Expulsions Fuses
Howard Industries isolation links are link body protects the link element compatible with mineral oil, seed-
intended for use with draw-out from handling damage that can cause based vegetable oil, silicone, and
expulsion fuses to provide additional nuisance open circuits inside the R-Temp® fluids.
protection during re-fusing opera- transformer.
tions. The internally-mounted Ordering IInformation
nformation
isolation link will melt during a low Dupont's Zytel® HTN polymer was To select the proper isolation link,
impedance transformer fault and chosen as the molding compound for refer to Page 2 for time-current
prevent line crews from re-energizing its excellent mechanical strength and characteristic curves and cross
a failed transformer. thermal characteristics. Zytel® is reference chart.
Isolation links are coordinated to
operate at the high current levels
experienced during a low impedance
transformer fault. Isolation links do
not have interrupting capabilty and
must rely on a series-connected
expulsion fuse for interruption of
fault current.
Design
Howard Industries isolation links are
designed to be bolted directly to the
lower connection tab of the expul-
sion fuse holder without the necessity
of removing any hardware, decreas-
ing assembly time for the transformer
manufacturer. The design of the
Zytel® is a registered trademark of Dupont. R-Temp® is a registered trademark of Cooper Industries, Inc.
Document No. 1026-01
Howard Industries Isolation Link
Minimum Melting Time-Current Characteristic Curves
(Isolation links were tested in transformer oil at 25° C)
Curve Number/Part Number Cross Reference Chart
Curve No. A1 A2 A3 A5 A6 A7
Part No. 0066-002812-811 0066-002812-812 0066-002812-813 0066-002812-815 0066-002812-816 0066-002812-817
Document No. 1026-01. Printed in USA. Howard Industries, Inc .
© 2003 Howard Industries, Inc. P.O. Box 1588
All rights reserved. Laurel, MS USA 39441-1588
www.howardtransformers.com
