ABB 07KT94‑S H3 (GJR5252100R2201) AC31‑90‑S Safety‑Related PLC CPU Unit

Product Description

07KT94‑S H3, order number GJR5252100R2201, is the safety‑enhanced basic CPU unit of ABB Advant Controller AC31‑90‑S platform, hardware revision H3. Compared with standard 07KT94, this is a TÜV‑certified safety‑oriented controller supporting mixed standard logic and safety‑related control functions. Supply voltage is 24 VDC, DIN‑rail TS35 mounting, IP20 protection. It acts as CS31 field‑bus master, supporting distributed CS31 remote I/O stations. Widely used on legacy machinery, waste‑gas abatement scrubbers, wastewater treatment and semiconductor fab auxiliary safety‑relevant skids.

Key Functions

• 32‑bit processor, program memory 240 kB, flash‑EPROM persistent program storage; supports Ladder Diagram, Structured Text; safety‑certified function block library available.
• On‑board mixed I/O: 24‑channel 24 VDC digital input, 16‑channel 0.5 A transistor digital output; 8 multi‑mode analog inputs, 4 analog outputs; analog channels support ±10 V, 0‑20 mA, 4‑20 mA, Pt100 RTD sensors.
• CS31 (RS‑485) field‑bus master, baud‑rate 187.5 kBaud; maximum 61 CS31 slave nodes on one bus segment, compatible with 07AC91, 07DI92, 07DO92 I/O modules.
• Dual isolated RS‑232 COM ports; for programming via 907 AC1131 software, Modbus‑RTU master/slave, ASCII host communication.
• Safety‑relevant I/O circuits, cross‑circuit monitoring for safety functions; TÜV approval for machine safety applications; safety and non‑safety logic can run on the same CPU hardware.
• Lithium backup battery retains retentive data, real‑time clock upon main power loss; front‑panel LED indicators: Power, RUN, STOP, System Fault, CS31 bus error, safety diagnostic status.
• Two high‑speed counter channels up to 50 kHz, built‑in PID control function blocks; operating temperature range: 0 °C ~ +55 °C, industrial EMC compliance.

Application Scenarios

• AC31‑90‑S distributed automation system as CS31 safety‑capable master controller.
• Semiconductor fab auxiliary equipment: abatement scrubber safety interlock, wastewater skid, gas cabinet local safety‑related sequencing control.
• Machine‑building with safety‑relevant requirements; packaging, material‑handling, process‑auxiliary control cabinets.
• Spare‑part replacement for legacy installed AC31‑90‑S systems; hardware revision H3 is a later production iteration of 07KT94‑S series.

Common Issues & FAQ

• CS31 bus fault / remote‑I/O stations drop‑off: Verify 120 Ω termination resistor fitted on both physical bus ends; eliminate station‑address conflict; inspect shielded RS‑485 cable routing and grounding; confirm stable 24 VDC supply for remote slave modules.
• Program loss / RTC reset after power‑cycle: Replace aged lithium backup battery; confirm application program saved to flash‑EPROM instead of volatile RAM.
• Safety‑related ERR LED active: Read PLC diagnostic buffer; check safety‑I/O cross‑monitoring faults, wiring short‑circuit, safety‑program runtime error or hardware failure.
• Cannot connect programming tool: Check RS‑232 cable wiring, RUN‑STOP switch position; match baud‑rate, parity and protocol in 907 AC1131 engineering software.
• Refurbished‑unit note: After replacement, download original user program including safety logic; validate CS31 bus‑node configuration; perform local‑I/O loop‑back test, full CS31 slave scan and complete safety‑function validation before commissioning. Check backup‑battery condition prior to production operation; hardware revision H3 must match project safety‑certification documentation.