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MDP Digital Time Overcurrent Relay GE Power Management
2 OPERATING PRINCIPLES GEK-100682D
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e) IOC DELAY
The Instantaneous unit can be delayed from 0.05 to 1.55 seconds. The time delay is the sum of the switches in
the right-hand position. For example, if only the third and fifth switches are in the right-hand position, the delay
would be 0.2 + 0.8 = 1 second.
f) COMMUNICATIONS ADDRESS
The address for the communications port is set via three rotary switches on the rear of the cradle unit. A setting
of 000 indicates no communications card is installed and disables the breaker status display. If breaker status
is desired and there is no communications card installed, any address other than 000 or 999 may be set. See
Figure 2–3: REAR VIEW SHOWING COMMUNICATION ADDRESS SWITCHES on page 2–3 for the location
of the communication address switches.
All MDP relays with the RS232 or RS485 protocol will respond to address 001.
g) OUTPUT CONTACT CONFIGURATION
The MDP relay has two output contacts that can be configured, by means of the output selection switch, allow-
ing the user to distinguish either between phase and ground, or between time delay and instantaneous.
In the A position on the nameplate, IOC phase and ground trips are output on studs 11/12 and 14/15, and TOC
phase and ground trips are output on studs 11/13 and 14/16.
In the B position on the nameplate, IOC or TOC ground trips are output on studs 11/13, and 14/16, and IOC or
TOC phase trips are output on studs 11/12 and 14/15.
CONTACT STUDS A B
K1a 11-12 IOC IOC or TOC Phase
K2a 11-13 TOC IOC or TOC Ground
K1b 14-15 IOC IOC or TOC Phase
K2b 14-16 TOC IOC or TOC Ground
NOTE
Courtesy of NationalSwitchgear.com