ICS T8800, Trusted 40‑Channel 24VDC Digital Input Field Termination Assembly (FTA)

1. Basic Information

2. Electrical Specifications

• Channel quantity: 40 digital input channels, 2‑wire field signal wiring
• Nominal field voltage: 24 VDC; operating range 18 VDC ~ 32 VDC
• Channel input current: 6.4 mA per channel
• Channel protection: Individual TR5 series 50 mA plug‑in fuse for each channel; field‑side short‑circuit only blows corresponding single‑channel fuse, no impact to other channels
• FTA power consumption: Passive termination assembly, no active on‑board power consumption
• Insulation: 500 VDC isolation, insulation resistance＞100 MΩ
• Terminal wire gauge: 12 AWG ~ 24 AWG
• On‑board indicator LED: Field power supply status LED
• Dual redundant 24 VDC field power input with diode OR‑ing circuit

3. Environmental Conditions

• Operating temperature: 0 ℃ ~ +60 ℃
• Storage temperature: ‑20 ℃ ~ +70 ℃
• Relative humidity: 5 % ~ 95 % RH, non‑condensing
• Enclosure rating: IP20 (cabinet‑mount installation only, not for direct hazardous‑area mounting)
• Approvals: IEC 61508 SIL‑3 system compatible, ATEX, IECEx, UL, CE certified
• Conformal coating: Not available. For offshore high‑salt‑mist projects, select conformal‑coated I/O module T8403C while keeping standard T8800 FTA.

4. Main Functions

1. 40‑channel field signal termination: Accept two‑wire 24 VDC discrete signals from field switches, pressure switches, level switches, smoke detectors, flame detectors and manual call‑points, interface to T8403 DI module.
2. Per‑channel independent fuse protection: Isolates field short‑circuit faults, protects T8403 I/O module hardware.
3. SmartSlot hot‑swap architecture: Back‑plane dual‑96‑way connector allows replacement of T8403 module without disconnecting field wiring.
4. Dual 24 VDC field power input with diode redundancy for improved power availability.
5. Power‑status LED for quick field‑supply troubleshooting.
6. Fully compatible with TMR 2‑out‑of‑3 safety architecture for ESD emergency shutdown and Fire&Gas safety loops.

5. Typical Applications

1. On‑shore and offshore platform SIS‑ESD emergency shutdown system for discrete digital input signal acquisition.
2. Fire & Gas safety system: interface for flame detectors, smoke sensors, manual fire‑alarm call‑points, pressure / level switch contacts.
3. Must only pair with T8403 / T8403C digital‑input module; incompatible with DO output modules.

Reference of Trusted T88xx series FTA

|FTA Part No.|Function|Matched I/O Module|

|—|—|—|

|T8800|40‑Ch Digital Input FTA|T8403 / T8403C|

|T8842|40‑Ch Configurable DI/DO FTA|T8448 / T8448C|

|T8850|40‑Ch High‑current DO FTA|T8451 / T8451C|

|T8861|40‑Ch 24/48 VDC DO FTA|T8461 / T8461C|

6. Important Notes

1. T8800 FTA itself has no conformal‑coated C‑version. For offshore projects use T8403C (conformal coated I/O card) with standard T8800 FTA.
2. Strictly compatible only with T8403 / T8403C 40‑channel DI module; do not mate with other model I/O modules.
3. Blown channel fuses must be replaced with TR5‑series 50 mA fuses.
4. Install inside certified control cabinet on DIN‑rail; cannot be mounted directly within hazardous zone.
5. Field 24 VDC power shall be provided externally for two‑wire input loops.