Product Overview
The F 3330 (F3330) is a high-reliability 8-fold output module engineered for safety-related industrial applications requiring Requirement Class AK 1 to 6. This module provides eight independent channels designed to drive resistive or inductive loads up to 500 mA (12 W), as well as lamp loads up to 4 W. It features integrated safety shutdown and safe isolation, ensuring that no output signal is present in the event of a break in the L- supply. Optimized for use in Emergency Shutdown (ESD) and Fire and Gas (F&G) systems, the F 3330 performs automated self-tests during operation, including "walking-bit" tests and signal read-back monitoring. These proactive diagnostic routines ensure high system availability and significant downtime reduction by detecting faults such as cross-talking or switching failures before they impact plant safety. Its robust design is ideal for critical infrastructure where fail-safe performance is a mandatory operational standard.
Technical Configuration
The F 3330 architecture is centered on safety-oriented diagnostics and fault tolerance. The module executes a continuous "reading back" of output signals to verify that the actual field state matches the commanded logic. For the 0-signal state, the read-back operating point is set at ≤ 6.5 V; faults arising below this threshold are managed through specific safety logic to prevent undetected failures. The integrated diagnostics include a test signal duration of maximum 200 µs, which is fast enough to verify switching capability without dropping the load or affecting process stability. Furthermore, the module supports paralleling of outputs without the need for external diodes, facilitating simple redundancy and higher current capacity configurations when required by the application logic.
Technical Specifications
| Attribute |
Specification Details |
| Model |
F 3330 |
| Brand |
HIMA |
| Origin |
Germany |
| Number of Outputs |
8 Channels |
| Load Capacity |
500 mA (Resistive/Inductive), 4 W (Lamp) |
| Internal Voltage Drop |
max. 2 V at 500 mA |
| Short Circuit Protection |
0.75 to 1.5 A operating point |
| Leakage Current |
max. 350 µA |
| Space Requirement |
4 TE |
| Power Consumption |
5 VDC: 110 mA / 24 VDC: 180 mA |
| Operating Temp |
0 to +60 deg C |
Technical FAQs
What happens to the output if the L- supply is interrupted?
The F 3330 is designed with a specific safety protocol that ensures no output signal is present if there is a break in the L- supply. This prevents unpredictable voltage potentials and ensures the module fails to a safe state.
Is it possible to drive higher wattage lamps with this module?
While the standard lamp connection is rated up to 4 W, it is possible to drive lamp loads between 4 W and 10 W by following specific HIMA planning sketches which typically involve external wiring modifications or current-limiting considerations.
At what voltage does the undervoltage tripping occur?
The module monitors the supply voltage and will initiate an undervoltage trip at ≤ 16 V to ensure that the outputs do not operate in an unstable or indeterminate state due to insufficient power.
Engineering & Installation Guide
Heat Dissipation and Rack Loading
During the planning phase, engineers must limit the density of high-load modules. A maximum of 10 output modules operating at nominal load should be used in a single I/O rack to prevent localized heat buildup. Maintain standard cabinet spacing to ensure unobstructed vertical airflow, which is critical for maintaining the operating temperature below the 60 deg C limit.
Wiring and Line Resistance
To ensure reliable short-circuit detection and accurate signal read-back, the total admissible line resistance (including both supply and return lines) must not exceed 11 Ohm. Use high-quality twisted pair cables for signal runs. While the module is short-circuit proof, excessive line resistance can prevent the short-circuit current from reaching the 0.75 to 1.5 A trip threshold, potentially masking a fault.
Vibration and Hazardous Area Precautions
In environments subject to mechanical vibration, ensure the module is fully seated in the subrack and that the fixing screws are properly tensioned. For installations in hazardous areas, the F 3330 must be housed within an appropriately rated enclosure (e.g., IP54 or higher) and installed in accordance with local intrinsic safety or flameproof regulations. Always verify that the 24 VDC external load supply is filtered and regulated to prevent transients from triggering the 200 µs test signal diagnostics.