Technical Specifications:

Functional Features:

• Four independently configurable channels — each can be set to current or voltage output independently
• 16-bit DAC resolution — 65,536 discrete steps for ultra-fine control
• Simultaneous update of all 4 channels at up to 10 kHz — critical for multi-axis synchronized control
• Linearization table — 16-point piecewise linearization per channel for non-linear actuator compensation
• Diagnostic per channel: overcurrent detection, open-loop detection, short-circuit detection
• LED indicators per channel for status monitoring (power, fault, output active)
• Galvanic isolation between all channels and the bus — eliminates ground loop issues

Structural Characteristics:

• Snap-in DIN rail TS35 mounting
• Spring-loaded push-in terminals for 0.14 mm² to 2.5 mm² wire
• Housing: glass-fiber reinforced polyamide (PA66-GF30)
• Four output connectors on the front, each with dedicated LED
• Rear X20 bus connector

Working Principle:
Each channel contains a 16-bit Digital-to-Analog Converter (DAC) that converts the digital value from the X20 bus into an analog voltage. For current output mode, this voltage drives a precision current loop circuit (Howland pump or transistor-based) that forces a proportional current through the load regardless of load resistance (within compliance limits). For voltage output mode, the DAC output is buffered by a low-impedance operational amplifier. The 16-point linearization table stored in the module’s memory corrects for DAC non-linearity and actuator non-linearity (e.g., equal-percentage valve characteristic). All four channels are updated simultaneously via a shared update trigger from the bus master.

Advantages & Highlights:

• 16-bit resolution (65,536 steps) — far superior to 12-bit modules (4,096 steps) for precision applications
• 10 kHz simultaneous update — all 4 channels change at exactly the same instant, essential for synchronized valve/drive control
• Per-channel current OR voltage — mix current and voltage outputs on the same module (e.g., 2× 4-20mA + 2× 0-10V)
• 16-point linearization — compensates for non-linear actuators without burden on the controller
• Full galvanic isolation — each channel is isolated from every other channel and from the bus

Applicable Industries:

• Process automation (control valve positioning: 4-20mA to I/P transducers)
• Variable frequency drive speed control (0-10V to VFD)
• Hydraulic proportional valve control
• Temperature control (0-10V to heater SSR)
• Batch dosing and mixing
• HVAC damper and valve control

Installation Requirements:

• Mount on DIN rail TS35 near the field devices for short analog cable runs
• Use shielded twisted-pair cable for current outputs (4-20mA); shielded coaxial or twisted-pair for voltage outputs (0-10V)
• Maximum cable length: 50 m (current, 4-20mA), 20 m (voltage, 0-10V) — longer runs require shielded cable with driven shield
• For current output: ensure total loop resistance (wire + load) ≤ 500Ω (4-20mA) or ≤ 250Ω (0-20mA)
• Connect 24V DC bus power from the X20 bus coupler

Usage Precautions:

• Do not exceed 500Ω total loop resistance on current outputs — the module cannot maintain current above compliance voltage
• Do not short-circuit voltage outputs — this can damage the output amplifier
• Do not leave voltage outputs unloaded (below 2 kΩ) — this causes instability and oscillation
• Set the correct output range (0-20mA vs 4-20mA) in the configuration — wrong range causes 25% offset error
• Enable linearization only when needed — incorrect linearization table causes output errors