Type FS-9 Closed-Link Test
Functional Description and
The Type FS-9 Closed-Link Test System, in combination
with a watthour reference standard, is used for testing watthour meters in the field. The
primary purpose of the FS-9 is to test Class 100 and 200, 240 volt, single-phase,
three-wire watthour meters (ANSI Forms 2 and 4) with the links closed. The FS-9 can also
be used to test Forms 1 and 3 and some polyphase meters. Knopp precision transformers
provide two isolated and identical currents necessary for closed-link, three-wire testing.
These transformers also supply the reference standard with a constant 5 amperes regardless
of the selected current.
All tests are performed at unity power factor. An
"off" position is provided on the current select switch so that a creep test
(voltage only) can be performed. In addition to fuse protection, two neon lamps are
provided to indicate improper connection to the meter-under test.
The FS-9 is mounted in a fiber carrying case which also
includes space for the reference standard and for the FS-9 lead set. A removable tray
allows storage for miscellaneous user-supplied tools.
Full Load: 5, 15, and 30 amperes.
Light Load: 0.5, 1.5, and 3 amperes.
Meter Types Tested
120 volt, 2 wire
240 volt, 2 wire
120 volt, 3 wire and
240 volt, 3 wire