IS230TBCIH6C - Contact Input with Group Isolation Terminal Board

SPECIFICATIONS:

Part Number: IS230TBCIH6C
Manufacturer: General Electric
Series: Mark VI
Product Type: Group Isolation Terminal Board
Number of channels: 24
Excitation Voltage: 125 V dc
Power Consumption: 20.6 W
Power supply voltage: 28 V dc
Voltage Range: 14 to 32 V dc
Mounting: DIN-rail mounting
Technology: Surface mount
Operating temperature: -30 to 65°C
Size: 33.02 cm high x 10.16 cm
Repair: 3-7 Days
Availability: In Stock
Country of Origin: United States
Manual: GEH-6721

FUNCTIONAL DESCRIPTION:

IS230TBCIH6C is a Contact Input with Group Isolation Terminal Board manufactured and designed by General Electric as part of the Mark VI Series used in GE Speedtronic Gas Turbine Control Systems. The Contact Input with Group Isolation (TBCI) terminal board accepts 24 dry contact inputs wired through two barrier-type terminal blocks, with contact excitation power supplied directly to the board. Each input features noise suppression circuitry to protect against surges, transient voltages, and high-frequency interference, ensuring reliable operation even in electrically noisy industrial environments. Its group isolation design allows multiple inputs to share a common isolation barrier while preventing cross-talk, providing accurate and robust signal monitoring for complex control systems.

COMPATIBILITY:

The TBCI terminal board is fully compatible with the PDIA I/O pack and is designed to support a wide range of configurations, including simplex, dual, and Triple Modular Redundancy (TMR) applications, providing flexibility for various control system architectures. Depending on the system requirements, one, two, or three PDIA modules can be installed directly onto the TBCI, allowing seamless integration and efficient use of available I/O channels. For installations with the Mark Vle control system, it is essential to use the C version of the TBCI board, which ensures the correct mechanical alignment of connector JTI with the I/O pack’s mechanical support. This alignment is critical for maintaining proper electrical connections, minimizing mechanical stress, and ensuring reliable long-term operation of the control system.

INSTALLATION:

Connect the wires for the 24 dry contact inputs directly to two I/O terminal blocks on the terminal board. These blocks are held down with two screws and can be unplugged from the board for maintenance. Each block has 24 terminals accepting up to #12 AWG wires. A shield terminal strip attached to chassis ground is located immediately to the left of each terminal block.

In a simplex system, connect the TBCI to the PDIA I/O pack using connector JR1. In a TMR system, connect TBCI to the three PDIAS using connectors JR1, JS1, and JT1. The PDIAS plug into TBCI and attach to side-mounting brackets. One or two Ethernet cables plug into the I/O pack. Firmware may need to be downloaded. Connect TBCI to the contact excitation voltage source using plugs JE1 and JE2.

OPERATION:

Filters reduce high-frequency noise and suppress surge on each input near the point of signal entry. The dry contact inputs on TBCI_IC are powered from a floating 125 V dc (100-145 V dc) supply from the turbine control. The 125 V dc bus is current-limited in the power distribution module prior to feeding each contact input. The H2, H3, and H4 versions use lower voltages (refer to the section, Specifications).

The discrete input voltage signals pass to the PDIA I/O pack, which sends them through optical isolators providing group isolation and transfers the signals to the Mark VIe controller. The reference voltage in the isolation circuits sets a transition threshold that is equal to 50% of the applied floating power supply voltage. The tracking is clamped to go no less than 13% of the nominal rated supply voltage to force all contacts to indicate open when voltage dips below this level.

A pair of terminal points is provided for each input, with one point (screw) providing the positive de source and the second point providing the return (input) to the board. The current loading is 2.5 mA per point for the first 21 inputs on each terminal board. The last three have a 10 mA load to support an interface with remote solid-state output electronics. Contact input circuitry is designed for NEMA Class G creepage and clearance.

WOC maintains the largest inventory of replacement parts for GE Speedtronic Gas Turbine Control Systems, ensuring that you have quick access to critical components when you need them most. In addition to supplying unused and rebuilt boards backed by a full warranty, we also offer expert repair services for faulty or damaged modules, restoring them to reliable, OEM-grade performance. Our team of skilled professionals is available 24/7 to provide technical support and guidance for all your automation and control system requirements. Whether you need replacement parts, repairs, or advice on system integration, WOC’s experts are ready to assist. For detailed information on pricing, availability, and repair services, please reach out to our team directly by phone or email, and we will ensure a fast, dependable response tailored to your needs.

FREQUENTLY ASKED QUESTIONS:

How many PDIA modules can be connected to the TBCI?

Depending on system configuration, one, two, or three PDIA modules can be plugged directly into the TBCI. This allows the board to support simplex, dual, and TMR applications, providing flexible integration into various turbine control architectures.

Why is the C version required for Mark Vle systems?

The C version ensures correct mechanical alignment of connector JTI with the I/O pack support, which is critical for maintaining reliable electrical connections and minimizing mechanical stress. Without this alignment, long-term reliability and signal integrity could be compromised.

What voltage powers the TBCI inputs?

The dry contact inputs are powered from a floating 125 V dc supply (100–145 V dc), with current-limiting applied by the power distribution module. Lower-voltage versions (H2, H3, H4) are also available for specific applications.