ICS T8461C‑ Digital Output Module,40‑Ch,24/48VDC,Sourcing,Conformal Coated

1. Basic Information

2. Electrical Specifications

• Channels: 40‑channel solid‑state sourcing DO, full TMR triple‑path architecture, hardware 2‑out‑of‑3 voting
• Field load voltage: Per‑channel software configurable: 24VDC (18‑32VDC) or 48VDC (36‑56VDC). No hardware change. Mixed 24V /48V loops allowed within one module subject to power‑group constraints.
• Output rating: 0.75A continuous per channel. Divided into 5 independent power groups (8 channels each), max.6A per power group.
• Protection: On‑channel electronic latching short‑circuit & overcurrent protection. External channel fuses are not required. Minimum load current for line‑monitor: 50 mA.
• Backplane supply: 20‑32VDC; typical power consumption 22W, maximum 25W.
• SOE: On‑board hardware SOE with 1 ms time‑stamp resolution. Output state changes and loop faults are time‑stamped locally without consuming controller CPU resource.
• Isolation: 2500V impulse withstand opto‑isolation between field side and backplane bus; 250V isolation between individual power groups.
• Conformal coating: Full PCB conformal coating (G3 corrosion grade), protects against salt‑mist, condensation and corrosive industrial gas for offshore & marine service.

3. Front‑panel & Interface

• Front‑panel LEDs: Module OK, Fault, Active/Standby status; per‑channel status LED for direct visual output / fault indication.
• Rear side: Dual 96‑Way high‑density connectors interfacing to T8861 VFTA terminal assembly. Hot‑swap allows module replacement without disconnection of field cables.

4. Environmental Conditions

• Operating temperature: 0℃ ~ +60℃; Storage temperature: ‑40℃ ~ +70℃
• Humidity: 5‑95% RH, non‑condensing; IP20 for cabinet installation.
• ATEX rating: Ex ec IIC T4 GC. For installation inside hazardous‑area cabinets on offshore platforms and corrosive refinery sites.

5. Main Functions

1. Channel‑level hardware TMR 2‑out‑of‑3 voting: Each output channel uses three independent drive circuits. Single‑path faults are isolated automatically to eliminate single‑point‑of‑failure risk.
2. Software‑selectable 24V /48V output: Individual channel voltage configuration supports both 24 V and 48 V solenoid valves, reduces spare‑part variety.
3. Full‑channel loop diagnostics: With T8861 VFTA, line‑monitor can be enabled via software to detect open‑load, short‑circuit and insufficient‑load conditions. Fault events are uploaded with time stamps.
4. Hardware 1 ms SOE sequence‑of‑event logging, supporting post‑incident analysis for ESD and Fire&Gas systems.
5. Hot‑swap maintenance: Module replacement online without interrupting other channel operation.
6. Compatible with both main T8100 chassis and T8300 expansion chassis. T8300 chassis must be fitted with T8310 expansion processor.
7. Conformal coating protection: Extends service life under salt‑mist and corrosive atmospheric conditions.

6. Typical Applications

1. Offshore oil‑gas platform ESD emergency shutdown and Fire&Gas systems (T8461C is mandatory; T8461 B‑version shall not be used)
2. Offshore modules, FPSO, coastal refinery SIS for driving 24 V /48 V solenoid valves and audible‑visual alarm beacons.
3. On‑site locations with corrosive atmosphere, conformal coated C‑version is preferred for higher reliability.

Comparative Reference Table

|Part No.|Per‑channel current|Voltage|Conformal coating|Typical application|Matching VFTA|

|—|—|—|—|—|—|

|T8461|B‑version 0.75A|24/48V|No|Onshore ESD / F&G|T8861|

|T8461C|C‑version 0.75A|24/48V|Yes (G3)|Offshore / high‑corrosion ESD / F&G|T8861|

|T8448C|0.75A|24V only|Yes|Configurable DI+DO Fire&Gas mixed I/O|T8842|

|T8451C|2A high‑current|24V only|Yes|ESD high‑power shutdown solenoids|T8850|

7. Important Notes

1. T8861 VFTA terminal assembly is mandatory; field cables cannot connect directly to the module. T8461 and T8461C share identical VFTA hardware, no terminal modification needed.
2. When installed in T8300 expansion chassis, T8310 expansion processor must be present.
3. Firmware is strictly segregated between B‑version and C‑version. T8461(B) firmware must never be downloaded into T8461C. Mechanically pin‑compatible yet firmware‑incompatible; always verify part number for spare‑part replacement.
4. Line‑monitor function requires field load current >50 mA, otherwise open‑load fault will be triggered. Not suitable for ultra‑low‑current loads.
5. Output type: sourcing output. Mixed 24 V and 48 V channels can coexist in one module, but different voltage groups must not share the same VFTA power partition.
6. Conformal coating only protects PCB circuit boards. The module must be mounted inside certified hazardous‑area cabinets and shall not be exposed directly to hazardous atmosphere.