IS200TRPAH2A - PRIMARY TRIP AEP

IS200TRPAH2A is an Aeroderivative Turbine Primary Trip terminal board developed by GE. Do not inadvertently connect the 240 V ac and dc voltages in 240 V ac applications. The peak voltage will exceed the MOV rating, causing the device to fail. Most ac supplies have a grounded neutral, and if an inadvertent connection between the 125 V dc and the ac voltage is made, the sum of the ac peak voltage and the 125 V dc is applied to MOVs connected between dc and ground. In 120 V ac applications, however, the MOV rating can withstand the peak voltage without failing.

IS200TRPAH2A Features

As part of the Mark VIe control system, the board interface with PTUR / YTUR I/O packs and TTUR terminal boards. The following are the inputs and outputs:/p>

• Twelve passive pulse rate devices (four per R/S/T section) measuring turbine speed by sensing a toothed wheel. Alternatively, six active pulse rate inputs (two per TMR section)
• Two 125 V dc TMR voted output contacts for the trip coil to the main breaker coil.
• Four 24-125 V dc voltage detection circuits for trip string monitoring
• One 24-125 V dc 'Fail-safe' ESTOP input for disabling trip relays. Signals from TMR systems fan out to the PR3, PS3, PT3, JR4, JS4, and JT4 connectors.

Installation

• TTL pulse rate pick-ups, voltage detection, E-Stop, and the breaker relay are all connected to I/O terminal block TB1.
• TB2 is wired with passive pulse rate pick-ups. Each block is held together with two screws and has 24 terminals that accept wires up to #12 AWG.
• To the left of each terminal block is a shield termination strip connected to chassis ground. JP1 and JP2 enable or disable fanning of the R section pulse rate pickups to the S and T PTURs or YTURs.

System Design

• The TRPA board is intended for use in two different ways. When a TRPA terminal board is used to connect three PTUR or YTUR I/O packs to a TTUR terminal board, three cables with DC-37 pin connectors on each end can be used.
• The TRPA provides two contact-voted trip relay outputs, ESTOP, and four voltage sensors in this mode of operation.
• TTUR has the standard set of features described for that board. The TRPA speed inputs are inactive and should not be used with this board configuration.
• The TRPA board can also be used with three I/O packs attached to it directly. The speed inputs to TRPA become active paths into the I/O pack in this mode of operation, allowing for a single terminal board primary trip solution.

Trip Relays

• Trip relays are constructed from groups of six individual form A devices arranged in a voting pattern. A conduction path through the set will be established if two controllers vote to close. Because detecting a shorted relay is critical for maintaining tripping reliability, each set of relays has a sensing circuit installed.
• When the relays are commanded to open and voltage is applied across the relays, the circuit detects whether one or more relays are shorted. This signal is sent to the I/O pack, which generates an alarm.
• To avoid a false indication if one I/O pack votes to close the relay while the other two I/O packs vote to open, the TRPA sensing circuit uses relay commands from all three packs.

Configuration

• Jumpers JP1 and JP2 control the fanning of the four passive speed pickups in the R section to the PTURs or YTURs in the S and T sections.
• To fan the 4 R speed input to the other two TMR sections, place the jumper over the pin pairs.