ABB 07KR51 07 KR 51 Compact PLC Basic Unit

Product Overview

The ABB 07KR51 (Product ID: 1SBP260511R1001) is a compact PLC basic unit from the Advant Controller 31 (AC31) series. Featuring 8 digital inputs and 6 relay outputs, this controller is designed for small to medium-scale automation tasks where reliability and cost-efficiency are paramount. With 34 kB of user program memory, the 07KR51 delivers robust performance for machine control, process monitoring, and building automation applications.

Key Specifications

• Manufacturer: ABB
• Product ID: 1SBP260511R1001
• Type: AC31 PLC Basic Unit
• Digital Inputs: 8 channels, 24 V DC
• Digital Outputs: 6 channels, relay type
• User Program Memory: 34 kB
• Power Supply: 24 V DC / 230 V AC (variant dependent)
• Operating Temperature: 0°C to +55°C
• Storage Temperature: -40°C to +75°C
• Mounting: DIN rail EN 50022-35 or 4 × M4 screws
• Protection Rating: IP20

Features & Benefits

• Integrated I/O: Built-in 8 DI / 6 DO eliminates the need for separate I/O modules in small applications, reducing cabinet space and wiring costs.
• Relay Outputs: Relay-type outputs provide flexibility for AC or DC load switching up to 2 A per channel.
• CS31 System Bus Master: Functions as a bus master for decentralized automation, supporting up to 31 remote I/O stations.
• Multiple Programming Languages: Supports LD (Ladder Diagram), FBD (Function Block Diagram), SFC (Sequential Function Chart), and IL (Instruction List) per IEC 61131-3.
• Real-Time Clock: Built-in RTC for time-stamped events and scheduling functions.
• LED Diagnostics: Comprehensive LED indicators for input/output status and system diagnostics.

Typical Applications

• Packaging machinery and material handling
• HVAC control and building automation
• Water pump and compressor control
• Conveyor systems and sorting equipment
• Small-scale process control loops

Installation Guide

1. Mounting: Secure the unit on a 35 mm DIN rail (EN 50022) using the snap-fit mechanism, or fasten with 4 × M4 screws. Maintain vertical orientation.
2. Power Connection: Connect the appropriate power supply (24 V DC or 230 V AC depending on variant) to terminals L+ and M. Observe polarity for DC variants.
3. I/O Wiring: Wire digital inputs (24 V DC) and relay outputs to the removable screw terminals. Max conductor cross-section: 2.5 mm².
4. CS31 Bus Setup: If using remote I/O, connect the CS31 bus cable and set the bus address via the coding switch.
5. Programming: Connect a programming device via the serial interface and download the application using ABB's AC31 programming software.
6. Commissioning: Verify all I/O LEDs, test input signals, and confirm relay output operation before placing the system in RUN mode.

FAQ

Q: What is the difference between 07KR51 and 07KT51?
A: The 07KR51 features relay outputs (6 DO relay), while the 07KT51 uses transistor outputs (6 DO transistor). The KR variant is preferred for AC load switching; the KT variant offers faster switching for DC loads.

Q: Can the 07KR51 communicate with other PLCs?
A: Yes, via the CS31 system bus and optional communication modules (07KP90, 07KP93, 07MK92), the 07KR51 can exchange data with other AC31 controllers and external systems.

Q: What programming software is required?
A: ABB's AC31 programming tools (such as 907 AC 1131) are used to develop, download, and debug applications for the 07KR51.

Q: Is this unit suitable for outdoor installation?
A: No, the IP20 rating requires installation inside a protective enclosure. For outdoor use, select a NEMA/IP-rated cabinet with proper environmental controls.

Selection Tips

• Choose 07KR51 for AC load switching (motors, solenoids, contactors); choose 07KT51 for high-speed DC switching (sensors, LEDs, low-voltage coils).
• Verify power supply variant: 24 V DC or 230 V AC — order the correct model suffix.
• For applications requiring analog I/O, pair with 07AC91 or 07AI91 expansion modules via CS31 bus.
• Leave at least 20 mm clearance on all sides for adequate air circulation.
• Consider the 07KT97 for larger applications requiring more memory (480 kB) and built-in analog I/O.