REXA SMB9215-1E-1-7725

Technical Specifications

1. Product Type: Single-channel digital brushless servo drive amplifier, dedicated for REXA Electraulic electro-hydraulic actuators
2. Physical Dimension: 89mm (width) × 262mm (length) × 152mm (depth)
3. Net Weight: 2.2kg (4 lbs 12.8 oz)
4. Input Power Supply: 110VAC ~ 220VAC wide range alternating current, 50/60Hz
5. Control Command Input Modes:
   • Analog signal input: 4-20mA standard process control analog signal, valve position 0-100% linear correspondence
   • Digital bus input: RS485 Modbus RTU industrial bus, remote digital valve position setting and amplifier parameter reading and writing
6. Drive Motor Matching: Dedicated drive REXA actuator built-in small brushless servo motor, closed-loop valve position feedback control
7. Feedback Signal Input: Built-in actuator valve position potentiometer analog feedback signal, real-time collect actual valve opening value
8. Control Response Frequency: Up to 1kHz fast response frequency, adapt to rapid pipeline pressure and flow regulation demand
9. Communication Interface: Isolated RS485 Modbus RTU bus interface, support multi-amplifier parallel bus connection to realize centralized valve control
10. Environmental Working Parameters: Operating ambient temperature -20°C ~ +70°C; storage temperature -40°C ~ +85°C; relative humidity 10% ~ 95% non-condensing
11. Protection Functions: Built-in over-current, over-voltage, short-circuit, over-temperature hardware protection circuit, fault alarm contact relay output
12. Industry Certification: CE electromagnetic compatibility certification, RoHS environmental protection standard certification

Functional Features

1. Dedicated matching REXA Electraulic™ electro-hydraulic actuator patented Flow-Match hydraulic system, realize high-precision valve position modulation without hydraulic oil external circulation
2. Dual command input mode switching freely: Support field analog 4-20mA local control and Modbus bus remote centralized control, one-key switching through amplifier internal parameter setting
3. High-precision closed-loop valve position control: Real-time compare external valve opening command signal and actuator internal potentiometer actual position feedback signal, adjust brushless servo motor rotation direction and speed through digital PID algorithm, valve position control accuracy up to ±0.25% full stroke
4. No-power position holding characteristic: When the amplifier cuts off input power, the REXA actuator internal Flow-Match gear pump hydraulic system automatically locks the valve stroke position, no valve drift occurs after power failure
5. Built-in full set of actuator diagnostic functions: Real-time monitor servo motor operating current, valve position deviation, internal hydraulic system pressure, amplifier internal operating temperature; upload all diagnostic data to upper DCS/PLC system through Modbus bus
6. Isolated RS485 Modbus communication circuit: Communication circuit and power drive circuit adopt optocoupler complete electrical isolation, eliminate industrial field strong electromagnetic interference causing communication signal distortion and loss
7. Multi-layer safety protection logic: When over-current, over-temperature, short-circuit fault occurs, the amplifier immediately stops outputting drive current to the servo motor, simultaneously trigger fault relay contact closed output, send alarm signal to control room DCS system
8. Compact modular box structure: Independent sealed metal box design, can be installed on actuator side wall or cabinet DIN rail, convenient on-site equipment layout transformation

Working Principle

1. Command Signal Receiving Stage: The amplifier receives external valve opening adjustment command signal; the signal can be 4-20mA analog signal transmitted by DCS control room, or digital position command sent by upper control system through RS485 Modbus bus
2. Position Feedback Sampling Stage: The amplifier continuously collects the actual valve stroke position analog feedback signal from the potentiometer built inside the matched REXA electro-hydraulic actuator
3. Digital PID Closed-Loop Calculation Stage: The internal DSP digital processing chip compares the target valve opening command value and the actual feedback position value, calculates position deviation, adjusts the output drive current amplitude and phase to the brushless servo motor through PID closed-loop algorithm, control the motor forward/reverse rotation to eliminate position deviation
4. Electro-Hydraulic Actuator Drive Execution Stage: The amplifier output three-phase drive current drives the small brushless servo motor inside the REXA actuator; the motor drives the patented Flow-Match positive displacement gear pump to push hydraulic oil to the double-acting hydraulic cylinder, drive the valve stem to move up and down to adjust the valve opening stroke
5. Fault Diagnosis & Alarm Output Stage: The amplifier internal real-time monitoring circuit continuously detects power supply voltage, motor operating current, internal chip temperature, feedback signal circuit state; once abnormal fault condition is detected, immediately cut off motor drive output, close fault alarm relay contact, upload fault code information to upper control system through Modbus bus

Material & Structural Features

1. Outer Protective Housing: Sealed cold-rolled steel metal box, surface epoxy resin anti-corrosion spray coating, four-corner fixed mounting lugs reserved
2. Internal Power Drive Circuit Board: Thick copper industrial power PCB board, high-power power MOSFET drive tube, independent heat sink aluminum alloy radiator for power components
3. Main Control Digital Circuit Board: Multi-layer small signal PCB board, industrial DSP processing chip, optocoupler isolation chip between power circuit and control circuit, conformal coating moisture-proof and dust-proof protection
4. Wiring Terminal Structure: Multi-group screw-type isolated wiring terminal blocks, classified wiring areas for power supply, analog command, position feedback, RS485 communication, fault alarm relay; each terminal with anti-loosening spring gasket
5. Heat Dissipation Structure: Built-in passive aluminum alloy heat dissipation fins inside the metal box, natural air convection heat dissipation, no built-in cooling fan, reduce mechanical failure points suitable for explosion-proof industrial field
6. Sealing Structure: Box cover assembly with rubber foam sealing gasket, all wiring holes with rubber cable waterproof and dustproof sealing rings, standard IP20 internal cabinet protection grade

Installation Requirements

1. Two Optional Installation Modes:
   • On-actuator mounting: Fixed installation on the side wall of matched REXA electro-hydraulic actuator through reserved mounting lugs
   • Cabinet DIN rail mounting: Installed on standard industrial control cabinet 35mm DIN rail, vertical installation required
2. Installation Direction Restriction: Must be installed vertically; horizontal or inverted installation will affect internal natural convection heat dissipation, easily trigger over-temperature fault alarm
3. Wiring Classification Specification: Strictly separate power supply wiring, analog signal wiring, RS485 communication wiring into different wiring troughs; analog and communication signal cables must use shielded twisted pair cables, single-point grounding of shielding layer at cabinet ground bar
4. Ambient Installation Environment: When installed outdoors on the actuator side wall, must be equipped with additional rain-proof and sun-shade protective cover; cannot be installed in environment with long-term direct sunlight, rain splashing, corrosive chemical gas accumulation
5. Grounding Specification: Amplifier metal box ground terminal must connect to equipment safety protection ground wire with wire diameter ≥1.5mm² copper wire, eliminate static electricity and electromagnetic interference

Application Scenarios

1. Petrochemical refining production lines: Pipeline flow control valves, reactor pressure regulating valves, oil and gas mixing ratio modulating valves
2. Natural gas transmission and distribution stations: Gas pipeline pressure reducing control valves, storage tank pressure relief modulating valves
3. Thermal power, chemical energy storage power plants: Boiler water supply flow control valves, flue gas desulfurization pipeline regulating valves
4. Water treatment industrial sewage treatment stations: Chemical reagent dosing flow control valves, sewage pipeline pressure regulating valves
5. Offshore oil and gas platforms, LNG storage terminals: Flammable and explosive medium pipeline precise modulating valve drive control

Operation & Maintenance Precautions

1. Before power-on commissioning, must complete valve stroke full range calibration operation according to REXA official manual; uncalibrated amplifier cannot realize accurate closed-loop position control
2. Do not open the amplifier metal box cover during power-on operation; live opening will expose high-voltage power circuit terminals, have electric shock safety hazard
3. Regularly clean the internal heat dissipation fins of the amplifier every six months, remove accumulated dust to avoid poor heat dissipation triggering over-temperature fault shutdown
4. When modifying valve control parameters through Modbus bus, must stop the valve adjustment operation first; parameter modification during stroke movement will cause valve jitter and overshoot
5. The matched REXA electro-hydraulic actuator internal hydraulic oil adopts standard automobile 5W-50 engine oil, no need to replace hydraulic oil within the whole service life of the actuator, do not add other types of hydraulic oil privately
6. If the amplifier repeatedly reports position deviation fault, check whether the actuator internal position feedback potentiometer wiring is loose or damaged, replace the potentiometer if signal collection is abnormal
7. Spare amplifiers for backup storage must be placed in dry constant temperature warehouse, all wiring terminal blocks covered with dustproof plastic protective caps to prevent dust and moisture corrosion of circuit board pins