Description
The HIMA F3335 is a high-reliability, 4-channel discrete output module engineered for deployment within H41q and H51q safety-related automation systems. It functions as an actuator driver interface within safety instrumented systems (SIS), emergency shutdown (ESD) architectures, and burner management systems (BMS). The module is certified up to Safety Integrity Level 3 (SIL 3) in accordance with IEC 61508 and EN 954-1 Category 4 standards.
Commercial Availability & Terms
- Condition: New Original (Factory Sealed Surplus) or Refurbished (Tested and Certified)
- Warranty: 12-Month Comprehensive Industrial Safety Warranty
- Availability: In Stock
- Standard Lead Time: 1–2 business days for priority international express courier dispatch
- Pricing Note: Pricing is dependent on current stock availability, certification testing dates, and component lifecycle phase. Contact our technical sales engineering desk for a binding, formal quotation.
Technical Specifications
| Parameter | Value / Specification |
| Safety Classification | Certified up to SIL 3 (IEC 61508) / Cat. 4 (EN 954-1) |
| Number of Channels | 4 independent, isolated safety discrete outputs |
| Nominal Output Voltage | 24 V DC (operational tolerance range +18 V to +33 V DC) |
| Output Current Capacity | 2 A continuous maximum per individual channel |
| Total Module Load Limit | 8 A maximum total load current at full deployment |
| Short-Circuit Protection | Onboard electronic current limiting with automated shutdown loop |
| Internal Safety Test Bus | Automatic line-monitored micro-testing executed every few seconds |
| Power Consumption | Approximately 5 V DC at 120 mA (logic side from central rack) |
| Form Factor | Standard HIMA 4U plug-in card for centralized I/O subracks |
Field Integration & Functional Safety Constraints
When integrating or executing maintenance on the F3335 module within an active safety loop, engineers must adhere strictly to these physical and software rules:
- Line Monitoring and Cross-Fault Detection: The F3335 executes integrated pulse testing to detect short circuits, wire breaks, and stuck-on component faults. A micro-second de-energization test occurs automatically. Ensure that the connected field loads (such as heavy-duty solenoid valves or trip coils) possess enough mechanical inertia so they do not chatter or trip during this brief test window.
- External Grounding Reference: The module relies on a solid, shared reference between the 24 V DC field supply common line and the HIMA central safety rack ground. If an isolated ground loop develops or if the field supply lacks a common reference point, the module will flag an internal safety switch fault, dropping all 4 channels to their designated fail-safe (de-energized) state.
- SIL 3 Redundancy Constraints: While individual channels can be used for safety circuits up to SIL 3, certain high-availability architectures require the module to be paired in a redundant configuration. When utilizing two F3335 modules in parallel for high availability, ensure the output decoupling diodes are properly rated to prevent a reverse-current fault from damaging the adjacent module if a field-side short circuit occurs.
Frequently Asked Questions
What happens inside the module when a short circuit occurs in the field?
If a channel detects an overcurrent condition exceeding its 2 A rating, the internal solid-state safety switch immediately opens to protect the module components and the field cabling. The specific channel’s front panel red error LED will illuminate, and an error flag is transmitted to the central safety processor. Once the physical field fault is corrected, the channel must be reset via the ELOP II or SILWorX engineering software environment.
Can the F3335 module be hot-swapped while the plant is operating?
Yes, HIMA H41q and H51q rack architectures support the physical extraction and replacement of I/O modules under power. However, pulling a single-channel (non-redundant) F3335 card will instantly de-energize its 4 associated safety loops, driving all connected field actuators to their safe state. For live, online hot-swapping without process interruption, the loop must be pre-configured in a redundant (duplexed) slot pairing.
How do I troubleshoot a persistent channel fault LED when the field wiring appears clean?
Disconnect the field connector block from the module and attach a dummy resistive load (such as a standard 24 V DC indicator lamp drawing at least 100 mA) directly across the faulted output channel terminals. If the module error LED clears, the issue resides in the field infrastructure (e.g., high line resistance or marginal leakage current to ground). If the red error LED remains lit with the field wiring isolated, the internal safety monitoring relays or output transistors have degraded, requiring a module replacement.
