Siemens Industry, Inc.
96
Neutral In:
U12
U112
NONE
Specifies which input is used for Neutral. Set to “NONE” if
tap changer lacks Neutral signal.
NeutralCount:
1 to 4
Specifies how many tap positions there are for “neutral”.
For certain LTC makes, there are 2 or more positions that are
“neutral”.
Note: Depending upon which changer is selected some of the configurable items may be locked from
changes.
Accumulating Input Data
The new algorithm will assimilate available data to make the best possible determination of tap position.
While the previous algorithm relied mainly on the motor signal current sensing for direction indication, the
new algorithm monitors and utilizes the following information:
1) Motor relay output (for automatic operations)
2) Motor signal current sensing
3)
The change in load voltage (“delta-V”).
Using the new algorithm
To use the new algorithm the user will select the tap changer type from the <Configure> menu, under
“TapChngr.” Once a tap type is selected some of the choices on the <Diagnostic> menu will become
locked because those features cannot be changed for that given type of regulator. If “Custom” is selected
then all tap configuration items on the <Diagnostic> menu become unlocked. The tap changer choices
are:
Siemens
Synchronization
Tap Change
Indication
Tap Direction
Indication
Active <Diagnostic>
Menu Items
Neutral Sense (U12)
closes to E; tap
position may be set at
front panel
Op Count (U10)
toggles (between
“U” and “E”)
Monitor current of
“J” and “K”,
Motor
relay output,
V
R/L On Time
R/L Off Time:
TapChgT/O
TapInPulse
PreTapTime
PostTapTime
GE
Synchronization
Tap Change
Indication
Tap Direction
Indication
Active <Diagnostic>
Menu Items
Neutral Sense (U12)
closes to E; tap
position may be set at
front panel
Op Count (U10)
quick pulse (“E” to
“U” to “E”)
Monitor current of
“J” and “K”,
Motor
relay output,
V
R/L On Time
R/L Off Time:
TapChgT/O
TapInPulse
PreTapTime
PostTapTime
