IS200TRPGS1B

IS200TRPGS1B is a Turbine Primary Trip Terminal Board for the Mark VIe series. The Gas Turbine Emergency Trip (TREG) terminal board is controlled by the I/O pack or control board and supplies electricity to three emergency trip solenoids (see table below). Between the TREG and TRPG terminal boards, up to three trip solenoids can be connected.

• TREG provides the solenoids with the positive side of the DC power, while TRPG gives the negative side. The I/O pack, also known as the control board, is responsible for emergency Overspeed protection, emergency stop functions, and the operation of TREG's 12 relays, nine of which are organized into three groups of three to handle the three trip solenoids.
• The PPRO pack on SPRO or TPRO is in charge of TREG. PPRO I/O packs link to SPRO or TPRO through D-type connections. TREG is connected to the terminal board through cables with molded plugs.

IS200TRPGS1B Installation

The first I/O terminal block is wired directly to the three trip solenoids, economizing resistors, and the emergency stop. The second terminal block can be wired with up to seven trip interlocks.

Operation

The PPRO / YPRO I/O pack or IS215VPRO board controls TREG completely. The J2 power cable and trip solenoids are used to connect to the control modules. A third cable runs from J1 to the TSVO terminal board in simplex systems, providing a servo valve clamp function when the turbine trips.

Control of Trip Solenoids

TRPG regulates the trip solenoids such that either one can cut power and close the steam or fuel valves with hydraulics. The PPRO / YRPO I/O pack or the IS215VPRO board provides 28 V dc to the nine-trip relay coils on TREG. With a 0.1 second L/R time constant, the trip solenoids are powered by 125 V dc via connector J2. They can draw up to 1 A.

The solenoids, which energize in the run mode and de-energize in the trip mode, are fed separately from the turbine control by a fused 125 V dc feeder. Diagnostics check the fuse integrity and cable connection of each 125 V DC feeder from the power distribution module at its point of entry on the terminal board.

Flame Detectors

Eight Geiger-Mueller flame detectors' signals are monitored by the main protection system. The flame detector charges to provide voltage in the absence of a flame. The detector charges up to a certain amount in the presence of flames before discharging through TRPG. The frequency of discharge rises as flame intensity does. The I/O pack/board and TRPG transform the discharged energy into a voltage pulse when the detector discharges. The range of the pulse rate is 0 to 1,000 pulses per second. All three units receive the same voltage pulses. A logic high is produced by voltage pulses above 2.5 volts, and a counter is used to track the pulse rate throughout a 40 ms time period.