Description
1. Product Overview
ABB SDCS-PIN-51, part number 3BSE004940R1, is a dedicated power measurement interface acquisition board matched with ABB DCS500 series thyristor DC speed controllers. Serving as the core for analog signal conversion and measurement between power units and SDCS-CON series main control boards, it is fully compatible with all DCS500 DC drive speed regulators. It undertakes isolation acquisition, voltage division conversion and signal transmission of multi-channel analog signals including armature current, excitation current, incoming line voltage, PTC motor temperature and thyristor power loop status, providing accurate raw measurement data for closed-loop control, overload protection and overheating interlock of the speed controller.
Equipped with high-precision voltage division sampling circuits, 12-bit ADC analog-to-digital conversion chips, multi-channel isolated signal loops and auxiliary RS485 communication interfaces, the board can receive secondary signals of current transformers and motor PTC thermistor temperature measurement signals, and convert high-voltage strong power signals from the power side into standard weak analog signals for the main control operation board. It works cooperatively with SDCS-CON-1/SDCS-CON-2 main control boards, integrating hardware filtering, surge absorption and wire breakage diagnosis functions. Adopting full-channel electrical isolation and industrial wide-temperature components without mechanical wearable parts. It is widely applied to DCS500 DC drive systems of metallurgical rolling mills, paper rewinders, port cranes, mine hoists, large water pumps and fans, for renovation projects such as adding temperature measuring points, replacing legacy measurement boards and upgrading high-precision current and voltage acquisition of drive systems.
2. Hardware Structure and Composition
2.1 Power Loop Signal Voltage Division Isolation Acquisition Unit
Multiple independent high-voltage isolated sampling loops are provided, which can be directly connected to the secondary side of main loop current transformers, three-phase incoming line voltage and armature loop sampling resistance signals. Each channel is equipped with precision voltage dividing resistors and transient absorption TVS components to attenuate high-voltage and large-current signals of high-power loops to a safe weak current range, with 1500VDC channel isolation withstand voltage. It completely blocks harmonics and surges from the power side from flowing back to the operation loop of the main control board and avoids breakdown of main control chips.
2.2 PTC Temperature Detection & Analog Conversion Unit
An independent dedicated PTC thermistor temperature measuring channel supports access to built-in PTC temperature measuring elements of motor stators and bearings, with a built-in constant current sampling circuit that converts resistance changes into standard voltage analog quantities in real time. It can accurately identify faults such as motor overheating, open circuit and short circuit of temperature measuring lines, and synchronously upload over-temperature signals to the main control board to trigger shutdown interlock protection.
2.3 12-bit ADC Analog-to-Digital Conversion & Data Cache Unit
A built-in 12-bit high-precision ADC conversion chip synchronously digitizes sampling of analog signals of various currents, voltages and temperatures. Sampling data is temporarily stored in on-chip RAM cache and uploaded to the SDCS-CON main control board through inter-board flat cables in real time to participate in speed and current dual closed-loop PI operation. Multi-stage digital filtering algorithms are embedded to eliminate sampling value jumps caused by field electromagnetic interference and improve measurement stability.
2.4 Inter-Board Flat Cable Communication & Status Indication Unit
Multiple groups of docking flat cable terminals are arranged on the side of the board for data interaction with the SDCS-CON main control board. Two-color LED indicators are mounted on the panel: PWR for power supply, RUN for sampling and FAULT for faults. Steady PWR light means normal board power supply; flashing RUN light represents normal transmission of ADC sampling data; illuminated FAULT light signals alarms such as broken temperature measuring wires, short-circuit of sampling loops and signal over-range, and fault codes can be read and traced via DriveWindow commissioning software.
2.5 Isolated Power Supply & Multi-Stage Hardware Protection Unit
Power is supplied by the internal 24VDC auxiliary power supply of the speed controller, with built-in isolated power conversion, filtering, reverse polarity and short-circuit protection circuits. Each sampling channel supports independent current limiting and overvoltage locking protection. A fault on a single channel will only block the sampling signal of the corresponding channel without interrupting measurement of other channels and the overall speed control logic, ensuring short-term safe operation of equipment.
2.6 Standardized Cabinet Built-In Modular Housing Unit
Flame-retardant V0 grade high-temperature resistant PCB substrate with reinforced component welding process, compact board size fixedly installed on the metal mounting base plate inside the speed controller cabinet. The bottom conductive buckle is tightly attached to the metal cabinet frame to realize integral shielding grounding. Gold-plated flat cable contacts resist oxidation and corrosion. Free of moving mechanical parts, it requires zero routine wear maintenance, adapting to long-term constant-temperature and continuous vibration operation inside sealed speed controller cabinets.
3. Technical Specifications
(1) Sampling & Measurement Performance Specifications
Model & Part No.: SDCS-PIN-51 / 3BSE004940R1Compatible Speed Controller Series: Full range of ABB DCS500 thyristor DC drivesADC Conversion Accuracy: 12-bitMeasurable Channel Types: Armature current, excitation current, incoming line voltage, PTC temperatureCompatible Transformer Ratios: Standard current transformers of 2500:1 and 4000:1PTC Temperature Measurement Specification: Standard motor PTC thermistor (130℃ action threshold)Input Signal Range: 0~20mA / 4~20mA standard analog sampling signalsIsolation Withstand Voltage: 1500VDC electrical isolation between sampling channels and internal logic loopsDiagnosis Capabilities: Online real-time detection of sampling wire breakage, loop short-circuit, signal over-range and PTC overheatingAdjustable Minimum Sampling Cycle: 50ms
(2) Overall Electrical Specifications
Rated Supply Voltage: 24VDC (allowable range: 12~48VDC)Typical Overall Operating Current: ≤50mA @ 24VDCMaximum Overall Power Consumption: ≤2.4WMatching Main Control Boards: SDCS-CON-1, SDCS-CON-2Hot Swap Support: Hot swapping of boards is not supportedMatching Commissioning Software: ABB DriveWindow, DCS Tools
(3) Environmental Protection Specifications
Operating Temperature of the Whole Unit: -20℃ ~ +60℃Storage & Transportation Temperature: -40℃ ~ +85℃Relative Humidity: 5%~95% RH, non-condensing, free of acid and alkali corrosive gasProtection Class: IP20 (only for installation inside sealed speed controller cabinets)Pollution Degree: Class 2EMC Compliance: IEC 61000-4 series industrial Class A high anti-interference standardVibration Standard: IEC 60068-2-6, suitable for continuous vibration working conditions of rolling mills and lifting equipmentMaximum Operating Altitude: ≤2000m
(4) Mechanical Installation Specifications
Mounting Method: Fixed installation on metal grounding base plate inside DCS500 speed controller cabinetOverall Dimensions: L145mm × W108mm × T55mmNet Weight: Approx. 0.164kgSubstrate Material: High-temperature resistant flame-retardant PCB, gold-plated flat cable docking contacts
4. Product Functions and Features
Multi-channel high-voltage isolated power sampling provides accurate raw data for main control closed-loop operation
Integrated independent isolated sampling channels for current, voltage and temperature can directly collect high-power thyristor main loop strong electrical signals, which are delivered to the main control board after high-precision voltage division and analog-to-digital conversion. It supports speed/current dual closed-loop PI regulation, armature overload current limiting and motor overheating interlock protection, guaranteeing steady-state control accuracy and dynamic response performance of DC drives.
Dedicated PTC temperature measuring acquisition loop realizes graded protection against motor overheating
The independent constant-temperature sampling channel matches built-in PTC temperature measuring elements of motors to monitor real-time temperature of motor windings and bearings. It can distinguish three states: broken temperature measuring wire, slight motor overheating and severe overtemperature, and cooperate with main control programs to realize graded protection of early warning, deceleration and shutdown to avoid motor burnout.
Built-in digital filtering and hardware isolation suppress strong electromagnetic interference from high-power drives
1500VDC hardware electrical isolation combined with multi-stage digital filtering algorithms completely isolates commutation harmonics of thyristors, cabinet ground potential differences and reverse electromotive force interference from motors, eliminating random jumps of sampling values and oscillation of current control, applicable to high electromagnetic interference field sites of high-power DC drives in metallurgy and mines.
Full-link real-time fault diagnosis enables rapid location of power-side sampling line abnormalities
It real-time monitors faults including sampling wire breakage, secondary short-circuit of transformers, signal over-range and invalid PTC temperature measurement. Fault signals are synchronously uploaded to DCS and speed controller panels to generate fault records. Maintenance staff can quickly distinguish faults of power loops, sampling lines and board hardware, greatly shortening downtime maintenance duration.
Standardized DCS500 cabinet installation architecture facilitates compatible replacement during legacy system renovation
Unified installation dimensions, flat cable docking definitions and power supply specifications allow direct replacement of legacy SDCS-PIN-52 measurement boards without modifying power transformer and motor temperature measuring wiring. Measurement functions can be restored merely by re-docking flat cables with short equipment shutdown renovation time.
Wide-temperature long-term industrial-grade hardware adapts to special working conditions such as explosion-proof and marine environments
Stable operation in ultra-wide temperature range of -20℃~+60℃, with special certifications for marine ABS and explosion-proof Zone2. It can be used in DC speed control equipment for lifting drives on offshore platforms and chemical explosion-proof areas, supporting stable 24/7 uninterrupted operation all year round with low component aging rate and long service life.
5. Applicable Working Conditions and Application Scenarios
Power Industry: Collection of armature current and motor temperature for DCS500 DC speed controllers of thermal power, hydropower and photovoltaic auxiliary machines, precise measurement for closed-loop overload protection.Chemical & Petrochemical Industry: Sampling of incoming line voltage and excitation current for DC drives in refining and fine chemical production lines, stable closed-loop regulation of reaction kettles and conveying equipment.
Metallurgical Industry: Collection of power loop signals for DC main drives of steel rolling, sintering and dust removal lines, high-precision tension measurement of strip steel production.
Paper & Light Industry: Sampling of excitation current and motor temperature for multi-section DC drives of high-speed rewinders and coating machines to stabilize paper web tension control.Port Lifting Industry: Measurement of power loops for DC lifting/travel speed controllers of container ship-to-shore cranes and portal cranes, collection of torque signals for anti-slipping hook control.
Mining & Cement Industry: Current and motor overheating temperature acquisition for DC speed control devices of mine hoists and cement kiln main drives.
Special Working Conditions: Power measurement and acquisition systems for DC speed control cabinets in offshore platform lifting equipment and chemical Zone2 explosion-proof hazardous areas.Technical Renovation & Maintenance Projects: Rectification of sampling signal drift of DCS500 speed controllers, installation of motor temperature measuring functions, and overall replacement projects of aging SDCS-PIN series measurement boards.
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