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EATON CORPORATION Cutler-Hammer
Information Sheets 70C1454H02
5.0 Choosing the Reduction Setting
The Arc Flash Maintenance Switch is an eight position
rotary switch that has five unique settings. Setting R5 is
repeated four times. From the factory, the Magnum circuit
breaker is shipped with the Digitrip unit set to the R5
setting and with its arming switch set to the 0/1 position.
The 0/1 position means that it is locally OFF, but can be
remotely turned ON. The blue LED, if illuminated, provides
indication that the Maintenance Mode setting is armed per
one of the three methods described in section 3.0.
In general, the selection of one of the Reduction Settings
(R5 through R1) should be determined and selected by a
person who is experienced in power system analysis.
This setting choice normally does not change unless there
are future system modifications that could increase or
decrease fault levels at the circuit breaker location.
6.0 Tripping and Testing
The Maintenance Mode function will provide fast tripping
even when the regular Instantaneous is set to OFF. The
Instantaneous LED position is also used to indicate a trip
initiated by the Maintenance Mode setting. The LCD
display, if powered, will indicate this with four dashes.
The Maintenance setting, external wiring (if any) and
tripping functionality should be periodically verified by
primary or secondary injection current testing.
