The GE IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is a compact discrete input and output terminal board used within GE Industrial Control Systems. As a member of the TDBS board family, the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is designed for DIN-rail or flat mounting and works with the PDIO I/O pack. The I/O pack plugs into the D-type connector and communicates with the controller over Ethernet, with a single connection point for the PDIO and one or two network connections possible from the PDIO to the controller or controllers.
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board accepts 24 group-isolated contact inputs that are supplied with a nominal 24 V DC wetting voltage from an external source, with an operating range of 16 to 32 V DC. The contact inputs include noise suppression to protect against surge and high-frequency noise, and the board provides 12 form-C relay outputs while accepting different W-type option boards to expand the relay functions. All terminal board versions have pluggable terminal blocks, simplifying field wiring and maintenance.
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is identified by the GE part numbering convention used throughout the Industrial Control Systems product line. The "IS200" prefix identifies the board as a GE Industrial Control Systems product, with "200" specifically indicating that the board is a base-level assembly. The "TDBS" acronym identifies the board's functional designation as a Simplex Discrete Input/Output Terminal Board. The "H2" designation identifies the hardware group and the wetting voltage variant, while the "ABC" suffix identifies the artwork and functional revision combination. All digits are important when ordering or replacing any board, as boards of different revision levels may not contain identical hardware, and GE ensures backward compatibility of replacement boards while noting that different revision levels may not contain identical components.
This product introduction provides detailed technical information, functional descriptions, connector assignments, configuration guidance, and comprehensive specifications for the GE IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board, serving as an essential reference for control system engineers, maintenance technicians, and system integrators working with GE industrial control equipment.
Functional Architecture and Signal Processing
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is built around a flexible discrete input and output architecture that combines 24 group-isolated contact inputs with 12 form-C relay outputs, providing a comprehensive discrete interface for a wide range of field devices. The board performs several distinct functions that ensure reliable and accurate acquisition of discrete signals and control of relay outputs in electrically noisy industrial environments.
The 24 contact inputs of the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board are supplied with a nominal 24 V DC wetting voltage from an external source, with an operating range of 16 to 32 V DC. The threshold voltage is 50% of the wetting voltage, providing a well-defined and noise-immune switching point. Contact input currents are resistance-limited to 2.5 mA on the first 21 circuits and 10 mA on circuits 22 through 24, allowing the board to accommodate a wide range of contact types, from standard dry contacts to solid-state output devices. The 24 V DC supply on the TDBSH2A is current-limited to 0.5 A using polymer positive temperature coefficient fuses that can be reset, providing protection against short circuits and faults on the field wiring. Filters reduce high-frequency noise and suppress surge on each input near the point of signal entry, ensuring that only valid contact transitions are reported to the I/O processor.
The discrete input voltage signals go to the I/O processor, which passes them through optical isolators, converts them to digital signals, and transfers them to the controller. This optical isolation provides group isolation between the field wiring and the control electronics, protecting the control system from ground potential differences and electrical transients.
The 12 form-C relay outputs of the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board provide normally open, normally closed, and common contacts for each relay, along with a solenoid return circuit path for a solenoid that is powered by the relay board. The relay portion of the board does not change between groups H2, H4, and H6, only the contact input circuits change, so the relays may be used at any specified AC or DC voltage without regard to board group. The relay outputs have a maximum response time of 25 ms on and 25 ms off, a silver-nickel alloy contact material, and a contact life of 100,000 electrical operations and 5,000,000 mechanical operations.
Option Boards and Relay Expansion
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board accepts three option boards that expand the relay functions and provide additional power distribution and fuse protection capabilities. The option boards plug into the TDBSH2A connectors JW1 and JW2 and are held in place by the force of the connectors, simplifying installation and allowing the relay functions to be tailored to the specific application requirements.
The IS200WROBH1A option board turns the relay portion of the TDBS into the functional equivalent of an IS200TRLYH1B terminal board, providing fused and sensed power distribution to the first six relay outputs and dedicated power to the last relay output. Both sides of the power distribution on relays 1 through 6 are fused, allowing the board to be used in systems where DC power is floating with respect to earth. Fuse voltage feedback is compatible with 24 V, 48 V, and 125 V DC applications, as well as 120 V and 240 V AC applications. The WROBH1A option board includes six jumpers that are used to apply or remove power from a relay, with all six jumpers in place at the factory and removed when a relay is to be used as dry contacts without power distribution.
The IS200WROFH1A option board adds an optional fuse in series with the common connection for each relay output by using the solenoid terminal in place of the common. Isolated voltage sensing that is not polarity sensitive is provided for each fuse, and the fuse voltage feedback can be used for feedback from 9 to 240 V AC or from 12 to 125 V DC. With the alternate application of this board, if the fuse is removed from a circuit, the isolated voltage detector remains, and the fourth terminal may be wired to either the normally closed or normally open terminal to provide isolated contact voltage feedback. The I/O pack firmware has a configuration option to turn off fuse-blown alarm generation for a given relay if it is being used in this fashion.
The IS200WROGH1A option board adds fused power distribution for all twelve relay outputs, with isolated voltage sensing that is not polarity sensitive provided for each fuse. The WROGH1A has a default fuse value of 3.15 A, and there are no jumpers associated with this board. This option board is useful for applications that require individual fuse protection for all twelve relay outputs.
It is important to note that discrete output option boards such as the WROBH1A, WROFH1A, and WROGH1A are not HazLoc certified and shall not be used with TDBS or TDBT terminal boards in hazardous (classified) locations. Additionally, the TDBSH8A terminal board shall not be used with intrinsic safety barriers, and the TDBSH2A shall not be replaced with the TDBSH8A without first installing the ControlST software suite 4.05 or later.
Installation and Wiring
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is designed for flexible installation in standard industrial cabinets. The board plus a plastic insulator mounts on a sheet metal carrier that then mounts on a DIN rail, or optionally the board plus insulator mounts on a sheet metal assembly that then bolts in a cabinet. The connections are wired directly to two sets of 48-point terminal blocks, typically using #24 to #12 AWG wires. The upper set of terminals, TB1, connects to the relay portion of the board, and the lower set of terminals, TB2, connects to the contact input circuits. Shields should be terminated on a separate bracket.
For the TDBSH2A, TDBSH4A, and TDBSH6A boards, the wetting voltage output terminals are all connected in parallel and fed from the positive voltage applied to JE1 pin 1. It is permissible to run a single wetting voltage lead from the board terminal to a group of remote contacts and then bring the individual contact wires back to the inputs. Negative or return wetting voltage is supplied by JE1 pin 3. For the TDBSH8A, each wetting voltage output terminal is protected by a separate internal current limit resistor, so a separate wetting voltage lead must be run for each individual output.
The contact input connections are made to the 48 terminals on the lower portion of the terminal board, grouped as TB2, with contact wetting voltage provided to the board through the JE1 3-pin Mate-N-Lok connector on the lower portion of the board. The terminal assignments for the contact inputs are clearly defined, with each input having a corresponding wetting voltage terminal and input terminal, allowing straightforward field wiring.
Diagnostics and Fault Detection
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board provides comprehensive diagnostic capabilities that assist with system verification and fault isolation. The PDIO I/O pack monitors several functions on the TDBS, including the contact input wetting voltage, which is monitored and generates a diagnostic alarm if the wetting voltage drops to below 40% of the nominal voltage. The diagnostic alarm is set and latched, alerting the operator to a potential problem with the wetting voltage supply.
The TDBS provides diagnostic feedback to the PDIO indicating the state of each relay by monitoring an isolated set of contacts on each relay, allowing the control system to verify that each relay has operated correctly. When the WROB option board is used, isolated voltage feedback is used to detect fuse status for the six fuse pairs on the board. When the WROF option board is used, isolated voltage feedback is used to monitor each fuse, and if voltage is present and the fuse is open, a diagnostic is generated. The diagnostic may be disabled in the PDIO configuration should it be desired to use the feedback circuit with the fuse removed. When the WROG option board is used, isolated voltage feedback is also used to monitor each fuse, and if voltage is present and the fuse is open, a diagnostic is generated.
The terminal board connector has an ID device that is interrogated by the PDIO, with the connector ID coded into a read-only chip containing the board serial number, board type, and revision number. Any relay option card also contains an ID, and if a mismatch is encountered, a hardware incompatibility fault is created, preventing the system from operating with incorrect or mismatched hardware.
The fault detection capabilities of the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board also include loss of contact input wetting voltage and non-responding contact input in test mode, providing comprehensive coverage of the most common failure modes in discrete input and output circuits.
Configuration
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board has no jumpers or hardware settings on the board itself. Configuration is performed through the system software and the PDIO I/O pack, simplifying installation and reducing the potential for configuration errors. The option board WROBH1 includes six jumpers that are used to apply or remove power from a relay, with the jumpers removed from the board when a relay is to be used as dry contacts and power distribution is not desired. There are no jumpers associated with the WROFH1 board, and for each relay the inclusion or exclusion of a series fuse is determined by the terminal point used as the relay common. There are no jumpers associated with the WROGH1 board.
Application Suitability and System Integration
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is a versatile discrete interface that can be used in a wide variety of GE Industrial Control System applications. Its 24 contact inputs with 24 V DC wetting voltage make it suitable for monitoring limit switches, pressure switches, level switches, temperature switches, relay contacts, pushbuttons, and other discrete field devices. Its 12 form-C relay outputs provide normally open, normally closed, and common contacts for controlling pilot relays, interposing relays, contactors, solenoid valves, indicator lamps, and other discrete output devices.
The board's support for three option boards, the WROBH1A, WROFH1A, and WROGH1A, allows the relay functions to be expanded and tailored to the specific application requirements, providing fused and sensed power distribution, individual fuse protection, or fused power distribution for all twelve relay outputs. The option boards' isolated voltage feedback allows the control system to detect fuse status and relay state, providing comprehensive diagnostics for the discrete input and output circuits.
In GE Industrial Control System applications, the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board works with the PDIO I/O pack, which plugs into the D-type connector and communicates with the controller over Ethernet. The board's pluggable terminal blocks and clearly labeled connectors simplify installation, verification, and maintenance, and the comprehensive diagnostics, including wetting voltage monitoring, relay state feedback, and fuse status monitoring, ensure that faults are detected and reported.
The board's support for DIN-rail or flat mounting and direct cabinet bolt-on provides flexibility for different cabinet arrangements, and the use of #24 to #12 AWG wires accommodates a wide range of field wiring sizes. The shield termination on a separate bracket ensures proper shielding and grounding of the field wiring, contributing to reliable operation in electrically noisy industrial environments.
Maintenance and Lifecycle
The IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is designed for long service life with minimal maintenance. The board contains no moving parts other than the relays, and its robust construction and surface-mount technology ensure high reliability in continuous industrial operation. Routine maintenance consists of periodic visual inspection of the board, terminal blocks, and wiring, verification that the wetting voltage is present and within specification, and confirmation that the shield terminals are properly connected.
The board's diagnostic features, including the wetting voltage monitoring, the relay state feedback, the fuse status monitoring, and the onboard ID chip, simplify troubleshooting and ensure that the correct board and option cards are installed in each location. If the wetting voltage drops below 40% of nominal, the board sets and latches a diagnostic alarm, protecting the system from incorrect operation. If a fuse opens in one of the option boards, the isolated voltage feedback detects the open fuse and generates a diagnostic, allowing the maintenance technician to quickly identify and replace the failed fuse.
If the board requires replacement, the process is straightforward. After de-energizing the associated equipment and verifying that no power exists, the pluggable terminal blocks should be labeled and removed, and the board should be removed from its mounting. The replacement board should be installed in the same position, and the terminal blocks reconnected as labeled before returning the system to service.
GE Industrial Control Systems ensures compatibility of its replacement boards, even though boards of different revision levels may not contain identical hardware. When ordering a replacement IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board, provide the complete part number and description, the drive or system serial number, and the Material List (ML) number. The factory may substitute later versions based on availability and design enhancements, but backward compatibility of replacement boards is guaranteed.
Conclusion
The GE IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is a reliable, robust, and versatile discrete interface for GE Industrial Control Systems. Its 24 contact inputs with 24 V DC wetting voltage, its 12 form-C relay outputs, its support for three option boards that expand the relay functions and provide fused power distribution and fuse status monitoring, and its comprehensive diagnostics provide the flexibility and reliability required for a wide range of industrial discrete input and output applications.
With its pluggable terminal blocks, clearly labeled connectors, comprehensive diagnostics, and compatibility with the PDIO I/O pack, the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board is designed for easy installation, verification, and maintenance. Backed by GE's quality manufacturing, global support network, and commitment to backward compatibility, the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board continues to deliver the performance, durability, and reliability that industrial users expect from GE. Whether used in a new installation or as a replacement for an existing board, the IS200TDBSH2ABC Simplex Discrete Input/Output Terminal Board provides the discrete input and output functionality required for reliable and efficient control system operation.
