IS200TREGH1BDB GE IS200TREGH1B Turbine Emergency Trip

 

Both TRPG and TREG control the trip solenoids so that either one can remove power and actuate the hydraulics to close the steam or fuel valves. The nine trip relay coils on TREG are supplied with 28 V dc from the IS215VPRO. The trip solenoids are supplied with 125 V dc through plug J2, and draw up to 1 A with a 0.1 second L/R time constant.

A separately fused 125 V dc feeder is provided from the turbine control for the solenoids,which energize in the run mode and de-energize in the trip mode. Diagnostics monitor each 125 V dc feeder from the power distribution module at its point of entry on the terminal board to verify the fuse integrity and the cable connection.

 

Two series contacts from each emergency trip relay (ETR1, 2, 3) are connected to the positive 125 V dc feeder for each solenoid, and two series contacts from each primary trip relay (PTR1, 2, 3 in TRPG) are connected to the negative 125 V dc feeder for each solenoid. An economizing relay (KE1, 2, 3) is supplied for each solenoid with a normally closed contact in parallel with the current limiting resistor. These relays are used to reduce the current load after the solenoids are energized. The ETR and KE relay coils are powered from the IS215VPRO boards in each of the R, S, and T sections, which supply an independent 28 V dc source.

 

The 28 V dc bus is current limited and used for power to an external manual emergency trip contact, displayed as E-Stop. Three master trip relays (KX4, KY4, KZ4) disconnect the 28 V dc bus from the ETR, and KE relay coils if a manual emergency trip occurs. Any trip that originates in either the protection module (such as EOS) or the TREG (such as a manual trip) will cause each of the three protection module sections to transmit a trip command over the IONet to the control module, and may be used to identify the source of the trip.

 

In addition, the K4CL servo clamp relay will energize and send a contact feedback directly from the TREG terminal board to the TSVO servo terminal board. The servo terminal board disconnects the servo current source from the terminal block and applies a bias to drive the control valve closed. This is only used on simplex applications to protect against the servo amplifier failing high.

 

The IS215VPRO board runs diagnostics on the TREG board and connected devices. The diagnostics cover the trip relay driver and contact feedbacks, solenoid voltage, economizer relay driver and contact feedbacks, K25A relay driver and coil, servo clamp relay driver and contact feedback, and the solenoid voltage source. If any of these do not agree with the desired value, a fault is created.

IS200TREGH1B connectors JX1, JY1, and JZ1 have their own ID device that is interrogated by the IS215VPRO board. The ID device is a read-only chip coded with the terminal board serial number, board type, revision number, and the plug location. When the chip is read by the IS215VPRO board and a mismatch is encountered, a hardware incompatibility fault is created.