EPRO MMS6312 Dual-channel Speed / Phase Alignment Module (User Manual - No Diagram Version) I. Product Overview

MMS6312 is a dual-channel speed/key-phase monitoring module of the EPRO brand under Emerson. It is a core component of the MMS6000 TSI system and is used for monitoring the speed, zero speed, key-phase, rotation direction, and differential speed of rotating machinery such as steam turbines, compressors, and fans. It supports redundant operation mode and can be hot-swapped while powered on.

II. Model Meaning

MMS6312: Standard dual-channel speed / phase module (without expansion function)

III. Compatible Sensors

Electromagnetic induction sensor: PR6426/6423 series + CON021/CON011 preamplifier

Hall speed sensor: PR9376 series (e.g. PR9376/010-011)

IV. Technical Parameters

Measurement Performance

Number of channels: 2 independent channels (redundant / independent configuration)

Frequency range: 0 - 20kHz (supports 0 rpm zero speed)

Speed range: 0 - 99999 rpm (programmable)

Phase resolution: 1 pulse / revolution (single phase slot)

Accuracy: ±0.01% FS; Temperature drift: ≤ 50 ppm/℃

Input Signal

Induction sensor: -24VDC power supply, input -18 to -2V gap voltage

Hall sensor: 8 to 31.2VDC power supply, input 0 to 24V square wave pulse

Output Signal

Speed current: 2 channels 0/4 - 20mA (isolated, load ≤ 500Ω)

Phase pulse: 2 channels 24V active pulse (1 channel per channel)

TTL pulse: 2 channels 0 - 5V (front panel SMB interface + back panel terminal)

Alarm Output: 4 channels relays (normally open / normally closed, 250VAC/3A)

Electrical and Environmental

Power supply: +18 - +31.2VDC (redundant dual input, ≤ 10W)

Temperature: -20℃ to +70℃; Humidity: 5% to 95% RH (no condensation)

Size: 30 × 128.4 × 160mm; Weight: 0.32kg

Protection: IP20 (module); EMC: Compliant with IEC 61000-6-2/4

V. Working Modes

Independent Mode (Single Channel)

Channel 1/2 separately monitor the speed / phase of 2 axes

Applicable: Dual-axis independent monitoring, one-used-one-busy non-redundant

Redundant Mode (Dual Channels)

Channel 1 main measurement, automatically switch to Channel 2 in case of failure

Applicable: Over-speed protection, critical axis speed monitoring (requires parameter configuration)

Steering / Differential Mode

Dual-channel cooperation: monitor rotation direction, speed difference between two axes

VI. Wiring Definitions (Back Panel Terminals, 32 pins)

Sensor Input (Channel 1)

B02: Sensor signal (induction / Hall)

B04: -24V (induction preamplifier power supply)

B06: 0V (ground)

Sensor Input (Channel 2)

B08: Sensor signal

B10: -24V

B12: 0V

Phase / TTL Output

D14/B14: Channel 1 phase (24V)

D16/B16: Channel 2 phase (24V)

Z14/Z16: TTL pulse (0 - 5V)

Current Output (Speed)

Z18/B18: Channel 1 (0/4 - 20mA)

Z20/B20: Channel 2 (0/4 - 20mA)

Alarm Relay

OUT1 - 4: Programmable alarm (over-speed / zero speed / differential / steering) Power supply

+24V: +18 to +31.2VDC

GND: Power Ground

VII. Configuration (MMS6910 Software)

Basic Parameters

Channel Enable: Channel 1/2 (Independent / Redundant)

Sensor Type: Eddy Current (PR642x) / Hall (PR9376)

Gear Teeth: Number of teeth of the speed measuring gear (e.g. 60 teeth)

Range: 0 to Full Scale (e.g. 0 to 6000 rpm)

Output Mode: 0 to 20mA / 4 to 20mA

Alarm Thresholds

Over-speed: High Alarm / High-High Alarm (e.g. 5400 rpm / 5700 rpm)

Zero Speed: ≤ 1 rpm (Spindle Alarm)

Difference: Difference between two axes (e.g. ±50 rpm)

Direction: Forward / Reverse (Reverseable Setting) Advanced functions

Offset tracking: Compensation for gap drift of eddy current sensors

Steering reset: External pulse / software reset of steering indication

Sensor self-check: Breakdown / short circuit / abnormal gap detection

VIII. Installation and Commissioning

Mechanical Installation

Method: DIN rail (IMR6000 chassis)

Location: Away from the power cabinet, with good ventilation

Spacing: ≥ 20mm from adjacent modules

Connection Points

Sensor cable: Double shielding, single-point grounding (module side)

Eddy current sensor: CON021 preamplifier installed nearby

Hall sensor: PR9376 with a gap of 1.0mm, vertical tooth surface

Power-on Commissioning

Self-check: Green LED always on (normal), red LED flashing (fault)

Signal Verification:

Eddy current: 5.5mm gap, preamplifier output 0V, module shows normal

Hall: Rotating gear, pulse frequency = rotational speed × number of teeth

Calibration: Current output 4mA = 0rpm, 20mA = full scale, accuracy ≤ ±0.05%

IX. Fault Troubleshooting

No rotational speed display

Sensor: Wiring / power supply / abnormal gap (eddy current 5.5mm, Hall 1.0mm)

Configuration: Incorrect number of teeth / range

Module: Channel not enabled / incorrect sensor type selection

Rotational speed fluctuation / oscillation

Interference: Cable close to the frequency converter / motor, poor shielding and grounding

Gear: Tooth surface wear / dirt, material not soft magnetic steel

Power supply: Voltage unstable (≥ 18VDC)

Alarm triggered by mistake

Threshold: Set too low / too high

Offset: Eddy current sensor gap offset (enable offset tracking)

Connection: Shielded double-end grounding, interference introduction

X. Accessories and Selection

Standard Accessories: MMS6312 + PR6426/010-140 + CON021 (eddy current speed)

Hall Accessories: MMS6312 + PR9376/010-011 (Hall speed / phase alignment)

System Accessories: MMS6823 (communication), MMS6210 (extension), DCS/DEH