Description
Emerson KJ2004X1-BA1
Technical Specifications
- Number of Input Channels: 8 independent two-wire analog input channels
- Input Signal Type: 4-20mA two-wire transmitter current signal
- Supported Protocol: HART 5 and HART 7 communication protocol
- LocalBus Power Consumption: 12VDC, 150mA maximum
- Bussed Field Power Output: 24VDC, 300mA total output for field transmitters
- Per-channel field circuit rating: 24VDC, 32mA
- Isolation Mode: Galvanic isolation between field loop and DCS backplane circuit
- Operating Ambient Temperature: 0℃ ~ 60℃
- Storage Temperature: -40℃ ~ 85℃
- Relative Humidity: 5% ~ 95%, non-condensing
- Protection Grade: IP20
- Communication Bus: DeltaV LocalBus proprietary backplane bus
- Mechanical Form: Standard DeltaV rack plug-in card
Functional Features High-resolution analog-to-digital conversion circuit completes high-precision sampling of 4-20mA analog measurement signals. Integrated HART modem chip realizes bidirectional digital data exchange superimposed on analog current loop without extra communication cables. Galvanic isolation components separate field instrument loop and DCS internal control circuit, restraining surge voltage and common-mode electromagnetic noise induced by long field cables. Independent diagnosis circuit for each channel continuously monitors loop current and power supply status. Front-panel LED indicators display module power status, general fault alarm and real-time signal status of every individual input channel. Hot-swap mechanical design supports module replacement under non-critical process operating conditions without cabinet power-off. Supports remote reading of HART device variables, instrument self-check alarm and parameter configuration via DeltaV engineering workstation or handheld HART communicator.
Application Scenarios DeltaV DCS control cabinets deployed in chemical plants, oil refineries, natural gas processing stations, pharmaceutical manufacturing workshops, thermal power plants and sewage treatment facilities. It connects two-wire HART smart pressure transmitters, flow transmitters, liquid level transmitters and temperature transmitters for collection of key process variable signals.
Performance Parameters Analog signal acquisition accuracy maintains stable performance within full rated working temperature scope. Analog-to-digital sampling circuit filters high-frequency industrial electromagnetic interference superimposed on field signal loops. HART communication maintains reliable data interaction on long-distance shielded twisted-pair signal cables. Diagnostic circuit detects loop wire break, short-circuit and transmitter power loss fault rapidly. DeltaV LocalBus ensures stable transmission of measured process data and fault alarm events.
Material Composition Flame-retardant black engineering plastic front housing. Multi-layer flame-retardant glass-fiber epoxy printed circuit board. High-resolution analog-to-digital conversion chips, HART modem components, main microprocessor, galvanic isolation devices and LED status indicator lamps. Gold-plated copper alloy backplane connector with anti-oxidation plating layer. Matching terminal base consists of flame-retardant PA plastic and nickel-plated copper screw terminals.
Structural Features Compact plug-in card physical size matching DeltaV rack slot installation dimension. Front panel is equipped with power indicator light, fault alarm indicator light and eight separate channel status LED indicators. Built-in guide rails and spring mechanical latch firmly fasten module in rack slot and resist vibration inside control cabinet. Rear gold-plated multi-pin connector completes electrical connection with DeltaV rack LocalBus backplane. Bottom contact pins are precisely aligned to matched terminal base to achieve field instrument signal wiring termination. Module outer shell is provided with multiple heat-dissipation slots to realize natural convection heat dissipation.
Working Principle Module obtains working power from DeltaV rack backplane LocalBus, and outputs 24VDC loop power to field two-wire HART transmitters through terminal base and field cables. Field smart transmitters convert physical process parameters into 4-20mA analog current signal and feed back current signal to module input channel. Analog current signal passes through galvanic isolation circuit and enters analog-to-digital conversion unit to be converted into digital measurement data. HART modem component parses superimposed HART digital signal from analog loop to obtain instrument tag, calibration data and diagnostic alarm information uploaded by field transmitter. Digital measurement values and HART device information are transmitted to DeltaV main controller through rack LocalBus backplane bus. Real-time sampling circuit monitors current magnitude and power state of each channel loop continuously. When wire break, short-circuit or transmitter power-loss fault occurs, the module generates fault flag and uploads alarm information to DeltaV operator station.
Installation Requirements Insert module along rack guide rail into specified DeltaV rack slot and fully lock mechanical latch. Field HART transmitter wiring must adopt shielded twisted-pair cables, and cable shielding layer performs single-point grounding inside control cabinet. Analog signal cables shall maintain sufficient separation distance from high-voltage power cables to avoid electromagnetic interference coupling. Do not block heat-dissipation slots on module shell, keep unobstructed air circulation around module installation position. After hardware installation completes, finish module hardware identification and HART device parameter configuration download in DeltaV engineering workstation.
Precautions for Use Take anti-static protective measures during module handling; bare hands shall not directly touch gold-plated connector pins. Cut off field signal loop power before performing wiring modification work. Carry out measurement value verification and HART communication link test after module replacement. Check terminal screw tightening condition and cable insulation performance in regular cabinet maintenance work. Prohibit applying voltage exceeding rated range to analog input terminals. Do not disassemble module outer housing; no on-site maintainable spare parts exist inside module.
