GE Fanuc IC609TCU100B Timer Counter Setpoint Unit Series One Plus PLC Japan

GE Fanuc IC609TCU100B Timer Counter Setpoint Unit Series One Plus PLC Japan

The GE Fanuc IC609TCU100B is a Timer/Counter Setpoint Unit designed for use with GE Fanuc Series One Junior and Series One Plus programmable logic controllers. It provides four independently settable BCD (binary-coded decimal) setpoint registers via front-mounted rotary thumbwheel switches, allowing operators to dial in timer and counter preset values directly on the module without a programming device. The unit connects to the PLC backplane via a D-sub style edge connector and provides RUN and CPU status indicators on the front panel.

Specifications & What's Included

• Manufacturer: GE Fanuc
• Model / Part Number: IC609TCU100B
• Type: Timer/Counter Setpoint Unit
• Switch Banks: 4 BCD rotary thumbwheel switch banks (front-accessible)
• REF/REG Assignments: REF 620/674 – REG 564,565 | REF 621/675 – REG 566,567 | REF 622/676 – REG 570,571 | REF 623/677 – REG 572,573
• Compatible PLC Families: GE Fanuc Series One Junior (T/C REGs 620–623), Series One Plus (T/C REGs 674–677; REGs 564–573)
• Connector: D-sub style edge connector (left side)
• Indicators: RUN LED (green), CPU LED (red)
• Enclosure: Black plastic module housing with ventilation slots
• Country of Manufacture: Japan
• Date Code: 104
• Includes: Unit only — no cables or mounting hardware

Applications

The IC609TCU100B is part of GE Fanuc's Series One family of compact PLCs, a line of small programmable controllers introduced in the 1980s and widely deployed in light manufacturing, machine control, and industrial automation applications. The Timer/Counter Setpoint Unit allows machine operators to adjust timer and counter preset values directly from the front panel without modifying the PLC program, which is useful in production environments where timing or count targets change frequently — for example, adjusting batch counts or cycle times on packaging, assembly, or conveyor systems. The module reads the thumbwheel switch positions and presents them to the PLC CPU as register values that the ladder logic program can reference as preset setpoints. This style of operator-adjustable setpoint module was common in the 1980s and 1990s on small PLC platforms before touchscreen HMIs became prevalent, and it remains in use today on legacy Series One installations still running in the field.