MEGGITT VM600 machinery protection system (MPS)

MEGGITT VM600 MPS Mechanical Protection System Hardware

The VM600 series mechanical protection and status monitoring system is designed based on a 19 inch standard chassis (1U or 6U) and integrates multiple functional cards. This system is mainly used for vibration monitoring of rotating machinery, ensuring the safety of key equipment such as turbines, compressors, and generators during operation. VM600 MPS can operate independently (stand-alone) or achieve centralized management through networked configuration, meeting various application needs from simple protection to complex monitoring.

System Overview and Hardware Composition

The basic hardware components of VM600 MPS system include:

Chassis: ABE04x (6U, 19 inches) or ABE056 (1U, 19 inches) chassis.

Power module: RPS6U (applicable for ABE04x) or RPS1U (applicable for ABE056) chassis power supply.

Processing card pairs: MPC4/IOC4T (mechanical protection card pair) and AMC8/IOC8T (analog monitoring card pair).

Relay cards: RLC16 (16 way relay) and IRC4 (intelligent relay card, configurable as 4 DPDT or 8 SPDT relays).

Network Controller: CPUM/IOCN card pair (for networked chassis).Chassis and Backpanel

ABE04x system chassis (6U)

Size: 19 inch chassis, height 6U, depth varies depending on configuration.

Card slot allocation: There are a total of 21 VME slots (slot 0 to slot 20). Slot 0 is used for CPUM cards; Slot 1 and 2 are used for RLC16/IRC4; Slot 3-14 is used for processing cards such as MPC4/AMC8; Slot 15-20 is used for power modules and relay cards.

Backplane structure: including VME bus (P1), analog bus (P3), and P2/P4 direct connection channels.

ABE056 thin chassis (1U)

Size: 19 inch chassis, height 1U.

Card slot allocation: Limited slots, supporting MPC4/AMC8 processing cards and corresponding IOC cards.

Slot coding: The thin chassis assigns slot numbers to the rear card components through micro switches on the backplane.

Power module

RPS6U (applicable to ABE04x)

Version: Early version (300 W) and later high-power version (330 W).

Input type: AC input (115/230 VAC) or DC input (24/110 VDC).

Redundant configuration: Two RPS6Us can be installed to achieve power redundancy. When one power supply fails, the other can independently supply power to the entire machine.

Auxiliary Sensor Power Supply (ASPS): Optional module that provides power to external sensors.

RPS1U (applicable to ABE056)

Input type: AC or DC input version.

Power status relay: provides dry contact output for+5V,+12V, and -12V power supply in normal state.

Bus Architecture

The VM600 backplane integrates multiple dedicated buses to achieve signal interaction between cards:

VME bus: used for communication between CPUM and processing cards such as MPC4/AMC8 (not supported by MPC4SIL security version cards).

Tacho bus: an 8-wire bus used for transmitting speed and phase reference signals, supporting cross card sharing.

Open Collector Bus (OC Bus): 96 wires, divided into 6 groups (16 wires per group), used to transmit alarm signals from the IOC card to the RLC16 or IRC4 relay card.

Raw Bus: 64 lines (32 pairs of differential lines), used for sharing raw analog signals (such as vibration signals) or supplementing OC Bus alarm signal routing.

Detailed explanation of core processing card pairs

MPC4/IOC4T mechanical protection card pair

MPC4 card version

Standard version: Supports VME bus, all processing modes, suitable for standard protection systems.

Independent circuit version: Complies with CEI/IEC 60255-5 insulation coordination standard.

Safe version (MPC4SIL): No VME bus interface, can only be configured through RS-232, does not support tracking vibration Smax、 Dangerous bypass (DB), Trip Multiply (TM), and channel suppression functions are suitable for SIL level safety applications.

Signal input and processing

Measurement channel: 4 dynamic signal inputs (vibration, pressure), supporting voltage (1 V/V) or current (0.3245 V/mA) signals.

Speed channel: 2 speed/phase inputs, supporting proximity probes, magneto electric sensors, or TTL signals.

Signal conditioning: AC/DC component separation, DC component is used for OK system inspection (monitoring sensor health status), AC component is output after programmable gain amplifier, integrator, anti aliasing filter and digital signal processing (DSP).

Output interface:

Front panel BNC: RAW OUT (raw signal), TACHO OUT (TTL speed signal).

Rear panel IOC4T: 4-channel DC output (4-20 mA or 0-10 V, configurable), 4-channel local relays, differential raw signal output.

Alarm function: Each channel can be configured with four alarm levels: Alert+/- and Danger+/-, supporting delay, hysteresis, and alarm locking. Support adaptive monitoring (dynamically adjusting alarm thresholds based on parameters such as speed) and Direct Trip Multiply (external signal switching alarm coefficient).

OK system: Monitor the DC level of the input signal. If it exceeds the user set OK range (continuous>250ms), a sensor fault alarm will be triggered.

AMC8/IOC8T analog monitoring card pair

functional positioning

The AMC8/IOC8T card pair is mainly used to monitor quasi-static parameters such as temperature, pressure, liquid level, flow rate, etc.