4
D. MNPR™ Operating Modes
The MNPR™ can operate in many different modes. The top row of the
Programmer allows you to select the four common operation modes of the
MNPR™. Selecting any position of the top row, and pressing
ENTER
will revert
the MNPR™ to preset settings corresponding to each of the four modes.
1. Sensitive
(standard) - Press
A, 1
- This is the most common mode. The
MNPR™ will open the protector when reverse net power exceeds the
Sensitive Trip setting. It will close the protector when the transformer voltage
exceeds the network voltage by the Reclose Voltage setting, the phase angle
of that differential voltage is greater than the Reclose Angle and within the
close region.
2. Time Delay
- Press
B, 1
- The MNPR™ closes the protector identically to
Sensitive Mode. The open process is different. Once the specified reverse
net power, the Sensitive Trip, is detected the MNPR™ will wait the Time
Delay setting before opening the protector. If, during that period, the absolute
value of current of any phase exceeds the Instant Current setting, the
MNPR™ will immediately open the protector. The user can also program a
delay for the Instant Current called the Extended Delay.
3. Insensitive Trip
- Press
C, 1
- the MNPR™ closes the protector identically to
Sensitive and Time Delay Mode. The MNPR™ will open the protector only
when the net power flow of the sensitive mode is met and the absolute value
of the current of any phase exceeds the Insensitive Trip Current setting. The
user can also program a delay for the Insensitive Trip Current called the
Extended Delay.
4. Watt-Var
- Press
D, 1
- the MNPR™ closes the protector identically to the
other three modes. The MNPR™ trip region is rotated counter-clockwise to
ensure that the network protector will open under certain circumstances. The
user can program the current at which the MNPR™ will rotate the trip region,
the Watt-Var Current. In addition, the user can program the number of
degrees to shift the MNPR™ trip region the Watt-Var Angle.
E. Programming the MNPR™ CT Ratio
The CT ratio allows the MNPR™ to properly display network currents during
operation. For the MNPR™ to close a General Electric network protector
properly, it must know the CT ratio of the network protector.
To program the MNPR™ CT Ratio, press
A, 2
at the
“ETI _ _”
scroll. The
Programmer will instruct you to
“Press NEXT to View CT Ratios”
. When the
proper CT Ratio appears on the display, press
ENTER
to program the MNPR™.
To verify CT Ratio on relay use Relay Status.
