ABB TCC300, User Manual, Page: 458 / 716

6.4.1.3
Shaft Coupled KeepTrack
™
tap position knowledge
Applicable controls and accessories for both Shaft Coupled KeepTrack Methods include:
• TCC300 Tapchanger Controls
• M-2025B(D) Current Loop Interface
• M-2948 Tap Position Sensor OR INCON 1292 Synchro Transmitter and 1250 Tap
Position Monitor
ABB Shaft Coupled KeepTrack Method
If Cam positions are not available and switches can not be retrofitted, a Shaft Coupled
KeepTrack method can be used. Most LTC tapchangers have an output shaft on the
tapchanger mechanism whose angular position is a mechanical analog of the tapchanger
tap position. For these applications, the following methods can be used to provide positive
tap position knowledge.
Figure 358 represents a typical application of the ABB Model M-2948 Tap Position
Sensor. The tap position sensor is a rotary shaft encoder with a built-in microprocessor
that provides stepped output signals in 9 or 10 degree increments. The tap position sensor
is available in both clockwise and counter-clockwise rotation configurations for
increasing tap position. It has rotations of 0° to 297°, 306°, 315°, 330°, 340° and 350°
degrees to accommodate tapchangers with 32 taps, 9 or 10 degrees per tap, and one to three
neutral positions.
M-2948
mounted on shaft
M-2948
Sensor
Control Cabinet
M-2025D
Current Loop
Interface
4-20 mA signal
TCC300
LTC Control
RS-485
or FO
HMI
Tap Position
RTU /
SCADA
.
.
Rx Current
Loop Resistor
Interface Cable
Transformer
GUID-1FAC051A-0E85-492A-9FF8-284FBA198723 V1 EN
Figure 358: Tap Position Scheme Using Shaft Coupled KeepTrack
Section 6
1VAC388793-MB A
Configuration
452 TCC300
User Manual