Description

Vibro‑Meter VM‑741B/TB1 Vibration Monitoring Module

Technical Specifications

• Part Number: VM‑741B/TB1
• Brand: Vibro‑Meter (Meggitt)
• Warranty: One Year
• Type: Single‑channel vibration monitoring module, TB1 = terminal‑block rear connector variant
• Power Supply: 24 VDC ±15 %; draws power from VM‑700 series rack backplane
• Input Sensor: Proximity probe (eddy‑current) / velocity transducer; supports dynamic vibration signal
• Measurement Functions: Vibration amplitude, gap/distance, alarm threshold setting; relay alarm outputs
• Frequency Range: 10 Hz‑10 kHz vibration bandwidth
• Accuracy: Amplitude reading ±2 % full‑scale
• Relay Output: 2‑set alarm relays (Warning / Danger); relay contact rating 250 VAC / 2 A resistive
• Analog Output: Buffered voltage output for recorder/DCS (0‑10 V proportional to vibration value)
• Operating Temperature: 0 °C ~ +55 °C rack‑mount; storage ‑20 °C ~ +70 °C
• Interface: Front‑panel LED alarm indicators; rear TB1 screw‑terminal block for sensor & alarm wiring; VM‑700 rack backplane connector
• Supported System: Vibro‑Meter VM‑700 series rack‑based machinery protection system (pre‑VM600 legacy platform)
• Protection: Over‑voltage input limiting; sensor breakage detection (probe fault, cable open/short); fault‑LED indication
• Dimensions: Standard VM‑700 rack slot size; weight approx 0.38 kg

Product Overview

The VM‑741B/TB1 is single‑channel vibration protection card for Vibro‑Meter legacy VM‑700 rack system. It acquires eddy‑current proximity‑probe signals, measures shaft radial vibration and probe gap value. It provides hardware‑level warning / danger alarm relays for machinery protection, and buffered analog output to send vibration data to DCS or chart‑recorder. Suffix TB1 means rear screw‑terminal‑block termination, no separate external terminal board required.

This module addresses rotating‑machinery protection challenges: hardware fast‑response vibration alarm protection, direct screw‑terminal wiring, drop‑in spare‑part compatibility for legacy VM‑700 retrofit‑maintenance projects. Turbomachinery protection engineers, power‑plant and oil‑gas‑site maintenance technicians and retrofit integrators benefit most. Widely used for steam‑turbine, gas‑turbine and centrifugal‑compressor shaft‑vibration monitoring loops.

Key Application Notes

• VM‑700 rack‑mount module; cannot operate standalone; must pair with matching eddy‑current proximity probe and VM‑700 power‑supply rack
• TB1 = screw‑block rear terminal variant; other variants use pin‑type connectors (TB2 etc); replacement spare must match suffix to fit existing cabinet wiring
• Sensor break detection monitors probe cable open‑circuit / short‑circuit faults
• Not hot‑swap capable: rack power must be removed before card replacement
• OEM original production is obsolete; only aftermarket surplus/refurbished spare available
• Conformal‑coated option for high‑humidity, high‑contaminant cabinet environments
• Commissioning must follow Vibro‑Meter VM‑741B manual for probe‑gap setup and alarm‑threshold calibration