Siemens MJ-4 Series User Manual

6 MJ-4A & MJ-4B Control Panel Automatic Mode
Siemens Energy, Inc. 53
NEUT R (Neutral Reverse)
This mode of operation is intended for use on systems
where reverse power flow is an abnormal situation.
In this mode, the controller always operates in the forward
mode. When current magnitude drops below the forward I
Threshold % setpoint, tap changes are inhibited. When
the reverse current magnitude exceeds I Threshold % set-
point for ten seconds, the tap changer resumes operation
and returns the tap changer to the neutral position without
stopping. The tap changer then remains at the neutral
position until forward current magnitude once again
exceeds the I Threshold % setpoint.
If, while the tap changer is returning to neutral, the for-
ward current magnitude increases above the I Threshold
% setpoint, normal forward tap changer operation
resumes.
Neutral Reverse mode is dependent upon the MJ-4
tap
tracking algorithm. If the tap position is unknown to the
microprocessor, the tap changer idles at the last held posi-
tion.
View Pwr Flow: NEUT R on the <CONFIGURE> Menu.
Figure 6.6 Neutral Reverse Mode
CO-GEN (Co-generation)
This mode of operation is for use on systems where
power flows from Utility to consumer at certain times and
from consumer to Utility at other times. In this mode, the
tap changer operates whenever current magnitude (either
forward or reverse) exceeds the I Threshold % setpoint.
In this mode, the controller always operates in Forward
mode. Forward Line Drop Compensation values are used
when forward current magnitude exceeds the I Threshold
% setpoint. Reverse Line Drop Compensation values are
used when reverse current magnitude exceeds the I
Threshold % setpoint. Tap changes are inhibited when
current magnitude is between the I Threshold % set-
points.
View Pwr Flow: CO-GEN on the <CONFIGURE> Menu.
Figure 6.7 Co-generation Mode
01% 1%
Threshold % Threshold %
Current
Return to
neutral
after ten
seconds
Forward
Operation
Reverse Current Forward Current
Tap Changes Inhibited
Band indicators flashing
I
I
RPF indicator on
Continue return
to neutral
RPF indicator off
Band indicator
LEDs on
01% 1%
Threshold % Threshold %
Current
Forward
Operation
with
Reverse
LDC
Forward
Operation
with
Forward
LDC
Reverse Current Forward Current
Tap Changes Inhibited
Band indicators flashing
I
I
RPF indicator on
RPF indicator off

Siemens MJ-4 Series Specifications

General

Brand	Siemens
Model	MJ-4 Series
Category	Control Panel
Language	English