F6705 is a dual-channel safety analog output module (AO) from the German HIMA company, designed for SIL3 safety instrumented systems. It outputs 0/4–20mA standard current signals, featuring safety isolation and shutdown functions. It has safety levels of AK1 to AK6. 

I. Core Parameters

Model: F6705 (Material Number: 984670501)

Channels: 2 analog output channels (electrical isolation between channels)

Output signals: 0–20mA, 4–20mA (software configuration)

Resolution: 12 bits (4095 steps)

Load capacity:

Source mode (Source): ≤ 550Ω (including line resistance)

Sink mode (Sink): ≤ ((UQ - 10V) / 2) / 21.2mA (UQ = 10~30V DC)

Accuracy:

Basic error: ≤ ±0.2% FS (40μA) @ 25℃

Operating error: ≤ ±0.4% FS @ 0~+60℃

Isolation withstand voltage: 250V AC (channel to analog ground)

Safety level: SIL3, AK1~AK6, Cat.4/PL e (TÜV)

Architecture: Safety redundancy, with integrated safety shutdown

Power supply: 5V DC ≈ 85mA; 24V DC≈130mA

Operating temperature: -20℃ ~ +60℃

Dimensions/Weight: 4TE (25×203×127mm) / Approximately 0.5kg

Installation: DIN rail, supports hot swapping

Diagnosis: Output short circuit / open circuit / over-range detection, automatic full test during operation

II. Main Matters (Installation / Wiring / Maintenance)

1. Installation Key Points

Environment: Dust-free, dry, without corrosive gases, anti-condensation

Heat Dissipation: Maintain a spacing of ≥ 50mm both above and below, keep away from heat sources and strong electrical equipment

Grounding: The cabinet has an independent protective ground (≤ 4Ω), and the system ground is separated from the protective ground

Hot Swap: Before online replacement, the module needs to be disabled in the software

2. Wiring Specifications (28-pin Terminal)

Signal Cables: Shielded twisted pair, single-ended grounding (module side), floating at the equipment side

Cabling Requirements: Separate the 220V/380V high-voltage power supply from the cable, with a spacing of ≥ 10cm, avoid long parallel runs

Maximum Cable Length: 1000m (load resistance needs to be verified)

Power Supply: 24V DC ± 10%, reliably connected to the module's GND

3. Configuration and Calibration

Software Configuration: Set the output type (0–20mA/4–20mA), range, and fault safety value through ELOP II

Calibration Cycle: Suggested once a year; if the error exceeds ±0.2% FS, re-calibration is required

Safety Shutdown: Automatically cuts off the output and enters a safe state upon a fault

4. Maintenance and Fault Troubleshooting

Status Indicators: Green LED = Normal, Red = Fault; Regularly check the diagnostic log

Common Faults:

Incorrect Output: Check the wiring, shielding, grounding, and load resistance

No Output from Channel: Check for short circuits / open circuits, replace the channel for testing, and if abnormal, replace the module