DS200PTCTG1A

DS200PTCTG1A is a Potential Transformer Current Transformer I/O board developed by Ge under the EX2000 excitation system. The primary function of the PTCT board is to isolate and scale voltage and current signals from PTs and CTs. It also has auxiliary inputs and outputs for low voltage (10 V dc) or current signals ranging from 4 to 20 mA.

Voltage Signals

Six high precision transformers with secondary ratings of 1.6 Vrms and primary nominal ratings of 120 Vrms are used on the PTCT board. On the PTCT, separate terminal points are provided for each primary connection. The voltage signals are measured using test points TPl through TP12.

Current Signals

The PTCT board contains three CTs, each with a burden resistor installed across the secondary. For each primary connection, a separate terminal point is provided. The voltage across the burden resistors RlO through RI2 is measured at test points TP13 through TP18.

Low Voltage or Current Inputs

Depending on the jumper settings on the PTCT, low voltage signal (10 volts) inputs can be converted to 4 to 20 mA signal inputs. The FTCT contains manually moveable hardware jumpers denoted by a BJ nomenclature.

Current Outputs

The 4 - 20 mA signals are sent from the PTCT board to the TCCB board via connector JKK.

DS200PTCTG1A Board Replacement

1. Turn off the exciter's power.
2. To remove the PTCT board, disconnect all cables carefully as follows:
1. When working with ribbon cables, place one hand on each side of the cable connector that connects to the board connector. Pull the cable connector gently with both hands.
2. Pull the pull tab carefully on cables with pull tabs.
3. Remove the screws that hold the board together at the top and bottom.
4. Place all configurable items on the replacement (new) board in the same position as those on the board being replaced (old board).