Model Interpretation

3700A: 32‑Ch TMR Analog Input, 0–5V +6% range, differential

P/N: 3700A (A = enhanced range version of 3700)

Compatibility: Tricon v9–v12 chassis (8110/8111/8112/8115/8116); hot‑swappable

Key Difference from 3700: 0–5V ±6% input range (3700 is strict 0–5V)

Technical Parameters

Electrical & Input

Input Type: Differential, DC‑coupled

Voltage Range: 0–5VDC ±6% (4.7–5.3V max)

Channels: 32, differential (non‑isolated channel‑to‑channel)

Resolution: 12 bits

Accuracy: <±0.15% FSR (0–60°C)

Input Impedance: ≥30MΩ (DC)

Response Time: <55ms (all channels updated)

Backplane Power: 24VDC, ≤15W (full load)

Isolation: 1,500VDC field‑to‑backplane galvanic isolation

Common‑Mode Rejection: ≥−80dB (DC–100Hz)

Redundancy & Safety

Architecture: Triple Modular Redundancy (TMR), 2oo3 voting

Safety Certification: IEC 61508 SIL3, TÜV, UL, CE, ATEX, FM

Diagnostics: Per‑channel continuous diagnostics; fault coverage >99.9%; SOE ≤40ms

MTBF: >150,000 hours

Mechanical & Environmental

Form Factor: 3U, 19” rack, 1 slot

Dimensions (W×H×D): 114 × 30 × 185 mm

Weight: ~1.2 kg (2.6 lbs)

Color Code: Dark Red (same as 3700)

Operating Temp: −40°C to +70°C

Storage Temp: −40°C to +85°C

Humidity: 5%–95% RH, non‑condensing

Diagnostics & Indicators

LEDs: PASS, FAULT, ACTIVE, TMR, ALARM

Fault Detection: Over/under‑range (extended to ±6%), TMR deviation, channel fault

Core Functions

32‑Channel 0–5V ±6% High‑Precision Input

Accommodates transmitter drift up to ±6% (vs. 3700’s strict 0–5V); ideal for real‑world sensors with minor output variation in safety loops.

TMR Fault‑Tolerant Analog Monitoring

Three independent measurement circuits with 2oo3 voting; eliminates single‑point failures for SIL3 ESD/F&G/BMS applications.

Extended Range Compatibility

The ±6% tolerance prevents nuisance trips from slightly out‑of‑spec transmitters—critical for remote or harsh installations where calibration drift is common.

High Noise Immunity & Isolation

1,500VDC field‑to‑backplane isolation and −80dB common‑mode rejection suppress ground loops and EMI in oil/gas/chemical environments.

Hot‑Swap & Online Maintenance

Replace module without shutdown; per‑channel diagnostics and SOE logging support IEC 61511 compliance.

Applications

Oil & Gas: ESD/F&G systems with 0–5V transmitters prone to drift; offshore platforms

Chemical/Refining: HIPPS loops; reactor/column analog monitoring with ±6% sensor tolerance

Power Generation: Turbine ESD; boiler BMS with 0–5V pressure/flow transmitters

SIS Retrofits: Drop‑in upgrade for 3700 where ±6% range flexibility is needed