100 percent of rated full-load current.
2.6.5.11
Terminals Pull Test
The purpose of this test is to determine whether the design of the filter
terminals can withstand the mechanical stresses to which they will be
subjected during installation or disassembly in equipment. Testing shall
be performed with the components mounted in the filter/ESA assembly
enclosure or mounted on a plate by the same holding method that will be
used for mounting in the enclosure. The force applied to the terminal
shall be 89 N 20 pounds. The point of application of the force and the
force applied shall be in the direction of the axes of the terminations.
The force shall be applied gradually to the terminal and then maintained
for a period of 5 to 10 seconds. The terminals shall be checked before and
after the pull test for poor workmanship, faulty designs, inadequate
methods of attaching of the terminals to the body of the part, broken
seals, cracking of the materials surrounding the terminals, and the changes
in electrical characteristics such as shorted or interrupted circuits.
Measurements are to be made before and after the test.
2.7
ELECTRICAL SURGE ARRESTERS (ESA)
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NOTE: ESA application guidance is found in MIL-HDBK
423.
**************************************************************************
2.7.1
Power and Signal Line ESA
2.7.1.1
ESA General
ESAs shall be metal oxide varistors (MOVs) or spark gaps. When a spark gap
is specified, the ESA shall be enclosed within a metal case. Discharges
shall be contained within the case; no external corona or arcing will be
permitted. ESAs shall be factory installed with minimum lead lengths
within the outer compartment. For all power filter/ESA assemblies, the
ESAs shall be installed a minimum of 75 mm 3 in apart, with terminals at
least 75 mm 3 in from a grounded surface. For telephone filter/ESA
assemblies, the ESAs shall have a minimum clearance spacing of 25 mm 1 in,
and terminals shall be at least 75 mm 3 in from a grounded surface. Each
phase, neutral and telephone circuit conductor shall be connected through
an ESA to the ground bus. The ESA shall be installed [in the power input
compartment of the filter] [in a separate EM shielded enclosure]. ESA
units within the filter/ESA assembly shall be individually replaceable.
Like ESAs shall be interchangeable. ESA terminals shall withstand the 89 N
20 lb pull test. Live parts shall be spaced in accordance with NFPA 70.
ESA leads shall be copper. Individual ESAs shall be marked with HCI tags
and shall be marked with the manufacturer's name or trademark and part
number. The ESA shall meet the requirements of IEEE C62.11, IEEE C62.41,
and UL 1449.
2.7.1.2
Wiring
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NOTE: Some designers prefer coiling the wire
between the ESA and the filter, because it creates
enough inductance to develop the ESA firing
potential during transients for HEMP applications.
Short leads, as recommended herein, improve the
SECTION 13095A
Page 38
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