Model Interpretation

3720TMR (3720): 64‑Ch TMR Analog Input, single‑ended, 0–5V/0–20mA

P/N: 3720 (TMR = triple modular redundancy)

Compatibility: Tricon v10.2–v12 chassis (8110/8111/8112/8115/8116); hot‑swappable

Key Difference from 3721: 64 single‑ended channels (vs. 32 differential on 3721); lower cost per channel; yellow color code

Technical Parameters

Electrical & Input

Input Type: Single‑ended, isolated; voltage or current

Voltage Range: 0–5VDC (±6% over‑range, 0–5.3VDC)

Current Range: 0–20mA (±6% over‑range, 250Ω shunt required)

Channels: 64, single‑ended; field‑to‑backplane isolation (≥800VDC)

Resolution: 12‑bit (standard) or 14‑bit (high) programmable

Accuracy: <±0.15% FSR (0–60°C)

Input Impedance: 140kΩ (DC, typical)

Over‑Range Protection: 150VDC / 115VAC continuous

Update Rate: 10ms (all channels)

Backplane Power: 24VDC, ≤12W

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

Redundancy & Safety

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

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

Diagnostics: Per‑channel continuous diagnostics (open/short, over‑range, TMR mismatch); fault coverage >99.9%; SOE ≤40ms

MTBF: >140,000 hours

Mechanical & Environmental

Form Factor: 3U, 19” rack, 1 slot

Dimensions (W×H×D): 114 × 30 × 185 mm

Weight: ~0.8 kg

Color Code: Yellow (high‑density AI identifier)

Operating Temp: −40°C to +70°C

Storage Temp: −55°C to +85°C

Humidity: 5%–95% RH, non‑condensing

Diagnostics & Indicators

LEDs: PASS, FAULT, ACTIVE, FIELD

Fault Detection: Over/under‑range, TMR deviation, channel open/short

Core Functions

64‑Channel High‑Density Analog Acquisition

64 single‑ended inputs for 0–5V or 0–20mA; ideal for high‑I/O safety loops needing cost‑effective, dense signal capture.

Programmable Precision (12/14‑bit)

Switch between 12‑bit (faster, standard) and 14‑bit (higher precision) to balance speed and accuracy in SIL3 applications.

TMR Fault‑Tolerant Safety Monitoring

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

Isolated & Robust Signal Conditioning

1,500VDC isolation and high CMRR suppress ground loops/EMI; built for harsh 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; high‑density pressure/flow monitoring (offshore/onshore)

Chemical/Refining: HIPPS loops; large‑scale reactor/column analog monitoring

Power Generation: Turbine/boiler ESD; BMS with dense sensor arrays

SIS Retrofits: High‑channel‑count upgrades for Tricon v10.2+ chassis