Description
The 8C-TDIL01 51306856-175 is a 32-channel, 24V DC digital input board (IOTA – Input/Output Termination Assembly) manufactured by Honeywell, designed as a core signal acquisition component for the Experion Series 8 / C300 distributed control system (DCS) platform. This high-density IOTA collects discrete on/off signals from field devices such as limit switches, pushbuttons, proximity sensors, valve position feedback contacts, and emergency shutdown (ESD) inputs, converting them into digital data for the C300 controller. The 8C-TDIL01 51306856-175 features galvanic optical isolation, G3 anti-corrosion coating, hot-swap capability, and three selectable scanning modes (Normal 20 ms, Fast 5 ms, and 1 ms SOE resolution), making it an ideal interface for safety-critical and high-speed event recording applications in demanding industrial environments.
Application Scenarios
In a Middle East petrochemical complex, the existing digital input IOTA boards in the C300-based emergency shutdown system (ESD) were experiencing frequent false triggering due to severe electromagnetic interference from nearby high-power compressors and variable frequency drives. The plant’s safety instrumented system (SIS) required a replacement that could maintain signal integrity while operating in a high-temperature, high-humidity, and corrosive atmosphere. By deploying the 8C-TDIL01 51306856-175, the engineering team leveraged its 1500 V AC RMS galvanic isolation between channels and the C300 backplane bus to effectively eliminate ground loops and EMI-induced noise. The module’s 1 ms SOE (Sequence of Events) resolution enabled pinpoint accuracy in reconstructing the exact order of valve closures and pump trips during a simulated compressor surge event, reducing root-cause analysis time from hours to minutes. For plant managers responsible for aging Series 8 installations, the 8C-TDIL01 51306856-175 — with its G3 anti-corrosion coating and -40°C to +70°C operating range — represents a robust, drop-in spare that keeps safety-critical architectures compliant and running without a costly platform migration.
Parameter
| Main Parameters | Value/Description |
|---|---|
| Product Model | 8C-TDIL01 51306856-175 |
| Manufacturer | Honeywell (USA) |
| Product Type | Digital Input IOTA Board (Termination Assembly) |
| System Platform | Honeywell Experion Series 8 / C300 DCS |
| Input Channels | 32 channels, independent optically isolated |
| Input Voltage | 24 V DC nominal (18–30 V DC operating range) |
| Input Current | ~7 mA per channel (typical) |
| ON Threshold | ≥ 15 V DC (ON sense voltage) |
| OFF Threshold | ≤ 5 V DC (OFF sense voltage) |
| Scan Modes | Normal 20 ms / Fast 5 ms / SOE 1 ms resolution |
| Isolation Rating | 1500 V AC RMS / ±1500 V DC (channel-to-system) |
| Diagnostic Features | Open wire detection, channel status monitoring, power/communication fault alarm |
| Field Power | Internal on-board excitation, or external 24 V DC selectable |
| Coating | G3 anti-corrosion coating (8C version) |
| Redundancy | Supports side-by-side redundant (dual IOTA) configuration |
| Operating Temperature | -40°C to +70°C (8C coated version) |
| Storage Temperature | -40°C to +85°C |
| Humidity | 5–95% RH (non-condensing) |
| Protection Rating | IP20 (panel/cabinet installation) |
| Dimensions (H×W×D) | 202 mm × 144 mm × 49 mm (9″ form factor, non-redundant) |
| Weight | Approx. 0.31 kg |
| Certifications | CE, UL, CSA, Class I Division 2, ATEX Zone 2 |
| Mounting | Series 8 I/O rack mounted, hot-swappable |
| Associated Processor | Pairs with 8C-PDIS01 for DISOE subsystem |
| Status Indicators | Per-channel LED + module health LEDs |