GE MDP User Manual

GE Power Management MDP Digital Time Overcurrent Relay 2
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GEK-100682D 2 OPERATING PRINCIPLES
2
2.9 DISPLAY AND RESET
The MDP relays are provided with a seven segment display, which can be scrolled without removing the cover,
by pushing the reset lever.
Upon energizing the relay, a value appears on the display that indicates the relay state. In order to differentiate
this from the rest of the information, it appears with the two decimal points illuminated. The values displayed
indicate:
•
.0.0
Equipment in Service
•
.0.1
Internal settings are different from the external settings
•
80
Fatal flaw
•
CL
Breaker closed
•
OP
Breaker open
Pushing the reset lever for less than two (2) seconds advances through a sequence of data. This sequence is:
•
F0
Current Breaker status (open, closed)
•
F1
Phase A current, in multiples of pickup
•
F2
Phase B current, in multiples of pickup
•
F3
Phase C current, in multiples of pickup
•
F4
Ground current, in multiples of pickup
•
F5
Phase A current multiples for the last trip
•
F6
Phase B current multiples for the last trip
•
F7
Phase C current multiples for the last trip
•
F8
Ground current multiples at the last trip
•
F9
Operating time for the last trip
Last trip data, F5 to F9, is retained, provided auxiliary power is maintained.
The two-digit display can show a maximum operating time of 99 seconds. When the time exceeds 99 seconds,
the MDP begins again from zero (0) with both decimal points lit to indicate the initial 100 units. If the time
exceeds 199 seconds, the display shows 99 with both decimal points lit.
When the reset lever is pressed for less than 2 seconds, the next function appears on the display. If, for exam-
ple, the phase A current is showing on the display and the lever is pushed, F2 appears, which indicates the
next function, and the moment the lever is released, the display will show the value of this function, which is the
B phase current multiples.
If the lever is held for more than 3 seconds, the In Service LED goes out and the relay initializes itself. The dis-
play shows the status function.
The relay can only be initialized if the input current is below pickup. If it has picked up, or has tripped and the
fault persists, the display will show the actual function when the lever is released, and it will not initialize.
If the reset lever has not been pressed for more than two (2) minutes, phase A current appears on the display.
Courtesy of NationalSwitchgear.com

GE MDP Specifications

General

Brand	GE
Model	MDP
Category	Relays
Language	English