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Tandem ELF current-limiting dropout fuse installation instructions
INSTALLATION INSTRUCTIONS
MN132029EN November 2016
CAUTION
Eaton’s Cooper Power series Tandem ELF Fuse is
designed to be installed in accordance with normal
safe operating procedures . These instructions are not
intended to supersede or replace existing safety and
operating procedures . Read all the instructions before
installing the Tandem ELF Fuse . The Tandem ELF Fuse
should be installed and serviced only by personnel
familiar with good safety practice and the handling of
high-voltage electrical equipment .
Product information
Introduction
Eaton’s Cooper Power series Tandem ELF current-limiting
fuse is designed for transformer protection. The Tandem ELF
fuse can be applied for fusing single-phase transformers
and for fusing three-phase transformers (or three-phase
banks of single-phase transformers). This fuse combines the
features of a series fuse link and a backup current-limiting
fuse in one package. The Tandem ELF fuse (refer to Figure
1) features a unique design for fast replacement of the
fuse link after a low fault current operation or excessive
transformer overload current or replacement of both the
fuse link and backup current-limiting fuse after a high fault
current operation. Note that when using recommended fuse
links or other properly coordinated fuse links, the fuse link
will operate to provide for the dropout action of the Tandem
ELF fuse following an interruption.
Read this manual first
Read and understand the contents of this manual and follow
all locally approved procedures and safety practices before
installing or operating this equipment
Additional information
These instructions cannot cover all details or variations
in the equipment, procedures, or process described nor
provide directions for meeting every possible contingency
during installation, operation, or maintenance. When
additional information is desired to satisfy a problem not
covered sufficiently for the user’s purpose, please contact
your Eaton representative.
Figure 1 . Tandem ELF fuse assembly
Upper contact
Upper pull ring
connector
Pull ring
Backup
current-
limiting
fuse
Fuse link
holder
Lifting eye
Fuse cap
Acceptance and initial inspection
Each Tandem ELF fuse is completely inspected and tested
at the factory. It is in good condition when accepted by
the carrier for shipment. Upon receipt of the Tandem ELF
fuse, inspect the connector thoroughly for damage and
loss of parts incurred during shipment. If damage or loss is
discovered, file a claim with the carrier immediately.
Table 1 . Recommended ELF current-limiting dropout fuse voltage ratings
Coordinates with fuse links up through
Backup current-
Limiting fuse
Edison
type D
Kearney
type X
Kearney
type QA
NEMA
type K
Kearney
Type 200
Edison
type N
NEMA
type T
Edison
type H
Kearney
type KS
25 K
20
10
30
25
20
30
15
8
7