I. Core Positioning

PI3381 is a dedicated pulse input I/O module for the Tricon SIS system, installed in the I/O slots of the mainframe / expansion frame; it adopts TMR triple redundancy, with three-channel synchronous sampling + hardware voting, responsible for rotational speed (turbo / compressor), flow rate (pulse flow meter), frequency, gear position counting, and is the core acquisition card for the safety monitoring of critical rotating equipment in high-risk industries, an indispensable SIL3-level pulse measurement card.

II. Specifications and Parameters (Official Standard Version)

1. Channels and Inputs

Number of channels: 6 isolated pulse inputs, common ground

Input type: compatible with differential / single-ended, supports magnetic-electric (passive), active (NPN/PNP), open collector sensors

Input frequency: 0.5Hz ~ 32kHz (up to 32,000Hz)

Rotational speed range: 0 ~ 32,000 RPM (gear speed measurement)

Pulse width: minimum 10μs, duty cycle 20% ~ 80%

Input amplitude:

Single-ended: 1Vpp (2~32kHz), 2Vpp (0.5~2Hz)

Differential: 0.5Vpp (2~32kHz), 1Vpp (0.5~2Hz)

2. Accuracy and Measurement

Resolution: 24-bit high-precision sampling

Accuracy: ±0.01% (high frequency), ±0.1% (low frequency)

Gear tooth count: 1~255 programmable, supports gear ratio tracking algorithm

Slope: Maximum 4,000Hz / second or 4,000RPM / second (60-tooth gear)

3. Redundancy and Safety

Architecture: TMR triple redundancy, three-channel independent sampling, hardware three-out-of-two voting

Safety certification: TÜV SIL3, CE, UL, CSA, ATEX

Isolation: 1500VAC isolation between channels, 1500VAC isolation on the backplane

Fault diagnosis: open circuit, short circuit, over-frequency, abnormal signal self-diagnosis

4. Electrical

Power supply: 24VDC (±10%), backplane redundant power supply

Power consumption: approximately 12W

Sensor power supply: 5V/12V/24V selectable, onboard short-circuit protection

5. Mechanical and Environmental

Size: 267 × 166 × 50mm (standard Tricon I/O size)

Weight: approximately 1.25kg

Installation: mainframe / expansion frame I/O slot, hot-swappable

Temperature: -40℃ ~ +70℃ (wide temperature, SIS standard)

Humidity: 5%~95%, no condensation

6. Panel Indicator Lights

PASS (green): module normal, redundant synchronization

FAULT (red): module / channel / redundant fault

ACTIVE (yellow): pulse signal acquisition active

FIELD PWR (green): sensor power supply normal

LOCK (yellow): parameter locked / configuration effective

III. Typical Applications

Rotational speed monitoring: turbo, compressor, fan, pump, etc. critical rotating equipment rotational speed / overspeed protection

Flow measurement: ** pulse flow meter (turbine / vortex) ** high-precision flow acquisition and accumulation

Position counting: gear position, encoder pulse, reciprocating machine stroke counting

Frequency measurement: grid frequency, vibration frequency, pulse signal frequency monitoring

Safety interlock: overspeed shutdown, low rotational speed interlock, low/high flow alarm, equipment protection