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The ABB SDCS-IOB-21 is a high-performance Input/Output Interface Module used within ABB’s DCS control and drive systems. It provides essential signal processing between the central control processor and the field devices, such as sensors, actuators, and communication interfaces.
Designed for precision and reliability, the SDCS-IOB-21 enables seamless transmission of both analog and digital signals in industrial environments. It features advanced electrical isolation, robust signal filtering, and diagnostic capabilities, ensuring optimal performance and operational safety even under challenging conditions.
This module plays a crucial role in maintaining communication integrity across the ABB DCS architecture, helping industrial systems achieve accurate process control, reduced downtime, and enhanced system flexibility.
| Parameter | Description |
|---|---|
| Model | SDCS-IOB-21 |
| Part Number | 3BSE005176R1 |
| Product Type | Input/Output Interface Board |
| Brand | ABB |
| Series | DCS Control System Series |
| Input Voltage | 24 VDC nominal |
| Digital Inputs | 16 isolated channels (24 VDC) |
| Digital Outputs | 16 transistor outputs (24 VDC, 0.5 A per channel) |
| Analog Inputs | 4 channels (0–10 V / 4–20 mA configurable) |
| Analog Outputs | 2 channels (0–10 V / 4–20 mA configurable) |
| Isolation Voltage | 2.5 kV between I/O and logic |
| Input Response Time | < 5 ms typical |
| Output Switching Time | < 3 ms typical |
| Protection Features | Overvoltage, short circuit, reverse polarity protection |
| Communication Interface | DCS System Bus / Internal Control Link |
| Diagnostics | Integrated LED indicators for status, error, and communication |
| Operating Temperature | 0°C to +55°C |
| Storage Temperature | −40°C to +70°C |
| Humidity Range | 5% – 95% (non-condensing) |
| Cooling Method | Natural air convection |
| Mounting Type | Rack or module frame mounting |
| Dimensions (W × H × D) | 190 mm × 125 mm × 40 mm |
| Weight | 0.72 kg |
| Compliance | CE, RoHS, and IEC industrial standards |
The SDCS-IOB-21 is engineered to serve as a robust and efficient interface module that bridges the logic control unit and field-level equipment. Within ABB’s DCS platform, it processes digital and analog signals, performing conversion, isolation, and routing tasks essential for system functionality.
Its architecture supports high-speed signal handling, ensuring precise and real-time data communication. The module’s design emphasizes durability, featuring reinforced electronic protection and industrial-grade components that withstand electrical disturbances, temperature variation, and mechanical vibration.
With its modular build, the SDCS-IOB-21 can be easily replaced or expanded without disturbing existing system wiring, significantly reducing maintenance time. It is fully compatible with ABB’s DCS drive systems, including DCS400, DCS500, DCS600, and DCS800 families, making it a dependable component for automation professionals.
Industrial DC and AC drive systems
Process automation in steel, cement, and mining industries
Paper and pulp manufacturing systems
Marine propulsion and electrical control platforms
Power generation and turbine control
Petrochemical and chemical process automation
Conveyor and hoisting control systems
Robotics and high-precision motion control environments
High Signal Reliability – Delivers accurate data transmission and minimizes communication errors through isolated and filtered channels.
Robust Electrical Protection – Features built-in surge and short-circuit protection to ensure long service life.
Modular and Serviceable – Compact form factor allows quick replacement, minimizing downtime during maintenance.
Versatile Signal Handling – Supports both analog and digital signal processing, accommodating multiple control system architectures.
Stable and Consistent Performance – Designed for continuous operation in harsh industrial environments.
Diagnostic Capability – Integrated LED indicators simplify system monitoring and troubleshooting.
Flexible Integration – Easily integrates into ABB’s DCS drive and control platforms without modification.
Compact Design – Lightweight and space-efficient for installation in dense system cabinets.
Compliance and Safety – Conforms to international industrial safety and reliability standards.
Proven Longevity – Engineered for long-term stability and minimal component degradation under industrial workloads.
Brand: ABB
ABB represents a global standard in automation and electrical control solutions. The brand’s DCS product series delivers exceptional precision, reliability, and control efficiency. Each module, including the SDCS-IOB-21, reflects ABB’s commitment to quality and industrial innovation, ensuring optimal performance across automation and drive systems worldwide.
Series: DCS Control System Series
The ABB DCS Control System Series integrates a comprehensive range of control, interface, and communication modules that form the backbone of ABB’s automation solutions. The SDCS-IOB-21 belongs to the Input/Output interface group within this family, enabling accurate and isolated data exchange between field devices and central processors.
| Model | Description | Key Parameters |
|---|---|---|
| SDCS-IOB-1 | Standard I/O Interface Board | 24 VDC input; 16 DI / 16 DO; Dimensions: 185×120×40 mm; Weight: 0.70 kg |
| SDCS-FIS-31 | Field Interface Board | 24 VDC; 4 analog channels; Dimensions: 185×120×35 mm; Weight: 0.68 kg |
| SDCS-FEX-4A | Field Excitation Board | Output: 0–500 VDC; 35 A; Dimensions: 200×140×45 mm; Weight: 0.82 kg |
| SDCS-CON-4 | Control Module | 24 VDC supply; Dimensions: 160×100×30 mm; Weight: 0.58 kg |
| SDCS-POW-3 | Power Supply Board | Input: 230 VAC; Output: 24 VDC; Dimensions: 190×120×45 mm; Weight: 0.80 kg |
| Model | Description | Key Parameters |
|---|---|---|
| ACS880-01-097A-3 | Industrial AC Drive | Power: 75 kW; Voltage: 400 V; Weight: 55 kg |
| DCS800-S02-0160-05 | High-Power DC Drive | 160 A, 500 V; Weight: 48 kg |
| CI858A | PROFINET Communication Interface | Voltage: 24 VDC; Weight: 0.50 kg |
| PM865K01 | High-Performance Processor Module | CPU: 32-bit; Voltage: 24 VDC; Weight: 0.55 kg |
| DSQC1047 | Automation Control Board | Voltage: 24 VDC; Dimensions: 210×130×40 mm; Weight: 0.70 kg |
Q1: What is the function of the SDCS-IOB-21?
A1: It acts as an Input/Output interface board that connects field devices with the control processor, enabling reliable signal communication and processing.
Q2: Which ABB systems is it compatible with?
A2: It is compatible with ABB DCS400, DCS500, DCS600, and DCS800 drive series.
Q3: How many input and output channels are available?
A3: The SDCS-IOB-21 has 16 digital inputs, 16 digital outputs, 4 analog inputs, and 2 analog outputs.
Q4: What is the operating voltage?
A4: The module operates on a 24 VDC power supply.
Q5: Does it provide electrical isolation?
A5: Yes, it offers 2.5 kV isolation between I/O and logic circuits for enhanced safety and noise immunity.
Q6: What kind of protection features are included?
A6: It includes surge suppression, overcurrent, short-circuit, and reverse polarity protection.
Q7: What is its operational temperature range?
A7: The operating temperature is from 0°C to +55°C, with storage between −40°C and +70°C.
Q8: How can I monitor system status?
A8: The integrated LED indicators display I/O activity, communication, and fault states.
Q9: Can this module be replaced without system reconfiguration?
A9: Yes, its modular design allows plug-and-play replacement within ABB DCS systems.
Q10: What are its dimensions and weight?
A10: It measures 190 mm × 125 mm × 40 mm and weighs approximately 0.72 kg.
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All product specifications are original and authentic imported products. We have an annual sales volume of 300 million yuan, and we only produce original and authentic products. All customers who cooperate with us directly online can enjoy low discounts.
Free warehouse
We have a complete range of product models, 80% of conventional models are in stock, and we have established channels in Asia, Africa, North America, South America, and Europe, effectively shortening the order processing time and satisfying customers in a timely manner.
Technical Team
Fast delivery. Spot goods can be shipped on the same day, and the delivery time transaction is 20% faster than that of peers on average, with a delivery time accuracy rate of 99%.
Thoughtful after-sales service
24-hour after-sales service guarantee team, professional and standardized management service system.