Product Introduction

Model Explanation

• 07: AC31 / Procontic 90/31 series

• KR: CPU with relay outputs

• 31: CS31 compact CPU platform

• Ordering options: 24VDC, 120VAC, 230VAC supply versions

Technical Parameters

• Power Supply: 24 VDC ±10% / 120 VAC / 230 VAC

• Current Consumption: ~400 mA (24 VDC)

• User Memory: 2 K words EEPROM (program)

• Onboard Inputs: 12 × 24 VDC, sink/source

• Onboard Outputs: 8 × relay, 2 A / 250 VAC

• High‑Speed Counter: 1 × 10 kHz

• Real‑Time Clock: Yes (battery‑backed)

• Communication:

  • RS‑232 (programmable, e.g., Modbus RTU)

  • RS‑485 (system bus, CS31 network)

• Operating Temperature: 0 °C to +55 °C

• Protection: IP20

• Dimensions (W×H×D): 125 × 88 × 25 mm

• Weight: Approx. 0.45 kg

• Certifications: CE, RoHS

Interface & Communication

• RS‑232: Point‑to‑point (HMI, SCADA, Modbus RTU slave/master)

• RS‑485: Multi‑drop CS31 bus; connects to remote I/O and other CS31 nodes

• LEDs: PWR, RUN, ERR, TX/RX

• Programming: 907 PC 331 software (DOS‑based)

Core Functions

1. Standalone Control: Executes ladder logic/structured text for small machines

2. Distributed I/O: Controls remote I/O via RS‑485 CS31 bus

3. Serial Communication: Links to HMIs, drives, or host systems via RS‑232/485

4. High‑Speed Counting: 10 kHz pulse input for encoders/pulses

5. Data Logging: RTC + EEPROM for timestamped data storage

Application Scenarios

• Packaging & Material Handling: Conveyors, small assembly lines

• HVAC & Building Automation: Chillers, pumps, fan control

• Water/Wastewater: Pump stations, small treatment plants

• Legacy System Retrofits: Replaces older CS31/07KR31 in existing plants

Usage & Maintenance

• Mounting: 35 mm DIN rail

• Wiring: 24 VDC power; shielded twisted pair for RS‑485

• Configuration: 907 PC 331; download via RS‑232

• Routine Checks: Verify LEDs; backup EEPROM program annually

• Troubleshooting: Check power, wiring, and bus termination; reload program if needed