Description:
The ABB 07CR41 (Order Code: 1SBP260020R1001, variant T3) is a Basic Unit / CPU Module from ABB’s Advant Controller 31 (AC31) 90-Series family of Programmable Logic Controllers (PLCs). It integrates a 32 KB program memory CPU, 8 isolated 24 V DC digital inputs, 6 relay outputs (250 V AC / 2 A) plus 2 transistor outputs, an RS-232 programming port, and a CS31 bus interface for communication with remote I/O or other AC31 masters/slaves. The 07CR41 is designed for standalone machine control, small process loops, and brownfield DCS auxiliary control tasks where a compact, rugged, and well-proven PLC platform is required.h2 Application Scenarios:A municipal wastewater treatment plant was facing repeated nuisance trips on a sludge-thickener rake mechanism controlled by an aging, unsupported panel-mounted relay-logic sequencer. The maintenance team replaced the obsolete hard-wired logic with the ABB 07CR41 (1SBP260020R1001), reusing the existing 24 V DC float-switch and limit-switch wires for the 8 DI channels and driving the rake-motor starter contactors via the 6 onboard relay outputs. The control logic — including timed rake reversal, jammed-rake alarm, and auto/manual mode — was programmed in ladder diagram using PG200 / Automation Builder. The 07CR41 restored full operational control in one planned downtime window, eliminated the intermittent contact-failure faults inherent to the old sequencer, and gave operators local status via panel lamps driven by the transistor outputs. This illustrates the 07CR41‘s practical value: a cost-effective, DIN-rail-mountable, time-proven PLC for modernizing small standalone machines or auxiliary process loops without the overhead of a full-scale DCS I/O rack.h2
Parameter:
| Main Parameters | Value/Description |
|---|---|
| Product Model | 07CR41 (Order No. 1SBP260020R1001, T3 variant) |
| Manufacturer | ABB (ASEA Brown Boveri) |
| Product Category | PLC Basic Unit / CPU Module — Advant Controller 31 (AC31) 90-Series |
| Program Memory | 32 KB — Sufficient for complex sequential, timer/counter, and PID logic |
| Digital Inputs (Onboard) | 8 × 24 V DC (PNP/NPN compatible, galvanically isolated) |
| Digital Outputs (Onboard) | 6 × Relay Output (250 V AC / 2 A, resistive), 2 × Transistor (24 V DC / 0.5 A) |
| Power Supply | 24 V DC (18–30 V DC), typical consumption ≈ 7 W |
| Communication Ports | 1 × RS-232 (PGU / programming / ASCII / Modbus Slave), 1 × CS31 Bus (max 500 m, 31 nodes) |
| Programming Standard | IEC 61131-3 (Ladder IL FBD SFC ST) via PG200 / Automation Builder |
| Max. Local Expansion | Up to 6 local I/O extension modules (DI/DO/AI/AO/Comm) |
| Operating Temperature | 0 °C to +55 °C (horizontal DIN-rail mount; derating may apply +60 °C) |
| Mounting | 35 mm Top-hat DIN Rail or screw-fixed base |
| Protection Rating | IP20 (cabinet installation only) |
| Dimensions (Approx.) | 110 × 115 × 86 mm (H × W × D) |
h2 Technical Principles and Innovative Values:
- Integrated I/O Eliminates Minimum Footprint Penalty: Unlike many PLC CPUs that require a separate I/O rack, the 07CR41 carries 8 DI + 6 relay DO + 2 transistor DO on-board. This means small machines can be automated with a single module — no backplane, no rack — drastically reducing panel space, wiring cost, and spare-parts inventory for standalone applications.
- CS31 Fieldbus for Scalable Distributed I/O: The built-in CS31 interface allows the 1SBP260020R1001 to act as a master polling up to 31 remote slaves (other AC31 units or dedicated CS31 I/O stations) over twisted-pair up to 500 m (extendable with repeaters). This provides a straightforward migration path from standalone to modest distributed control without stepping up to a full DCS.
- IEC 61131-3 Conformant & Long-Life Architecture: The 07CR41 runs proven ABB runtime firmware supporting all five IEC 61131-3languages. Programs developed decades ago remain uploadable/modifiable with current ABB tools, and the module’s industrial-grade design (wide supply tolerance, optical isolation on I/O, robust EMC performance) explains why many units installed in the 1990s are still in daily operation — a key advantage for plant life-extension projects.
h2 Application Cases and Industry Value:Case 1 – Cement Plant Cooler Grate Local Control Retrofit:A dry-process cement kiln’s cooler-grate vibratory feeder had its original electromechanical timer fail repeatedly due to dust ingress and contact wear. The plant installed a ABB 07CR41 (1SBP260020R1001) to implement variable-delay start/stop sequencing with local pushbutton overrides wired to its DI channels and the feeder contactor driven by a relay DO. The PLC’s sealed DIN-rail enclosure resisted the dusty environment far better than the old open-panel timer bank. After commissioning, unplanned stops due to control-logic failure dropped to zero over a 24-month observation period.
