Siemens MJ-5 Installation And Operation Manual page 55

6
MJ-5 Control Panel Automatic Mode
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 % set point, 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 % set point.
If, while the tap changer is returning to neutral, the forward
current magnitude increases above the I Threshold
% set point, normal forward tap changer operation resumes.
Neutral Reverse mode is dependent upon the MJ-5 tap
tracking algorithm. If the tap position is unknown to the
microprocessor, the tap changer idles at the last held
position.
View Pwr Flow: NEUT R on the <CONFIGURE> menu.
Figure 6.6 Neutral Reverse Mode
Siemens Industry, Inc.
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 % set point.
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 %
set point. Reverse Line Drop Compensation values are used
when reverse current magnitude exceeds the I Threshold %
set point. 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
51