Walker Industrial: Home > Manufacturers > Ametek Gemco > Linear Displacement Transducers > 953 VMAX LDT


The Need for automation is greater today than ever before.

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Linear Displacement Transducers (LDT) play an important role in factory automation. They provide accurate, reliable, absolute position feedback to help automate today’s sophisticated machinery. Sensors must deliver value, be easy to set up, and interface easily into the host controller.

We know the manufacturing challenges of today are extreme, so we designed and built a sensor to meet and exceed these demands, regardless of the application or environment. Innovation, proprietary technology and decades of experience were the key to the development of our 953 VMAX Linear Displacement Transducer.

The 953A VMAX is an accurate, programmable zero & span, auto-tuning, non-contact linear displacement transducer in a rod-style package. The transducer utilizes our field-proven Magnetostrictive technology to give absolute position, accurate to 0.01% of the programmable sensing distance. A variety of different outputs are available, including Analog (Voltage or Current), Digital (Start/Stop or PWM) and SSI (Serial Synchronous Interface). The 953 VMAX has a variety of truly unique features. The first one is the wide power range of 7 to 30 VDC @ 1 watt. The second is the LDT’s auto-tuning capability, the ability to sense a magnet other than the standard ring magnet and adjust its signal strength accordingly. All units have a diagnostic LED to display the health of the unit and to help aid in troubleshooting. Our Analog units offer programmable Zero & Span points, the analog output is programmable over the entire active stroke length. Units can be ordered in span lengths from 25mm to 7.6M in 1mm increments.

Introducing the 953 VMAX LDT features:
  • High Vibration Resistance to 30 Gs (lab tested)
  • High Shock Resistance to 1000 Gs (lab tested)
  • Wide Input Power Range of 7 to 30 VDC - (no need to specify different models for mobile applications)
  • Very Low Power Consumption, 1 Watt Typical, Allows Direct Connection to Display and Control Interface Modules
  • Applications Include All Mobile/Stationary Equipment, or both with the Same Sensor • High Accuracy with High Resolution – Resolutions to 1 micron
  • Sensor Lengths from 1” to 300” (25mm to 7.6M) • Durability and Reliability Exceeds Competitive Offerings
  • Tri-Color Diagnostic LED Indicator, Gives Quick Indication on the Status of the LDT • Removable Cartridge for Hydraulic Applications
  • SSI (Synchronous Serial Interface), 24, 25 or 26 Bit, Binary or Gray Code, Position Updates
  • Analog Output, 0-10 VDC, +/-10 VDC, 0-5 VDC, +/-5 VDC, 4-20mA • Digital Output, Start/Stop, Variable Pulse (PWM), Control Pulse
  • Multi-Magnet Option (Digital Start/Stop only)
  • Contaminant Resistant - IP68 Rated • Optional Stainless Steel Cover and Connector
  • Drop-in replacement for competitive model units – same Null, Dead bands, threads and connectors

Specifications for 953A, 953D, and 953SSI VMAX LDTs
953SSI Connector Interface

953D Connector Interface

953A Connector Interface
6 Pin 12mm Euro micro, Standard. Integral cable ass'y, 7 Pin or 8 Pin DIN - Optional

6 Pin 12mm Euro micro, Standard. Integral cable ass'y, 6 Pin or 8 Pin DIN or 10 Pin MS- Optional

5 Pin 12mm Euro micro, Standard Integral cable ass'y, 6 Pin or 8 Pin DIN or 10 Pin MS- Optional
Sensor Housing and Mounting Hex Body length 3.2”, hex base 1 3/4” dia., 3/4”x16x1” thread.
Aluminum housing standard, stainless steel optional.
Displacement 1” to 300"
Dead Band 2.50" (63.5 mm) standard, (2.25” Minimum)
Null Zone 2.00" (50.8 mm) standard, (1.5” Minimum)
Enclosure Rating IP68, IEC 600529
953SSI Resolution

953D Resolution

953A Resolution Internal Output
English or Metric Units Metric: 1, 5, 10, 20 micron (5 micron standard)
English: .00005", .0001", .0005", .001" Consult Factory for Others.

Controller Dependant

0.00006” 16-Bit
Shock 1000 Gs (lab tested)
IEC 60068-2-27
Vibration 30 Gs (lab tested)
IEC 60068-2-6
Guide Tube Pressure 5,000 psi continuous (10,000 psi spike)
Approvals CE (EMC)
Input Voltage 7 to 30 VDC
Current Draw 1 watt typical*, 40mA at 24 VDC typica
953A Zero & Span Adjustability Factory set at Null & Dead Band locations Field re-settable at any location within active stroke
953D Repeatability

953A Repeatability

953SSI Repeatability
Equal to Resolution of Controller

Equal to Resolution

Equal to Output Resolution
953SSI Measured Variables Single Magnet Displacement, Consult Factory for Velocity or Differential Operation
953SSI Output

953D Output

953A Output

953A Current Output

953A Voltage Output
24, 25 or 26 Bit, Binary or Gray Code (optional parity and error bit), Position Update

RS = RS422 Start/Stop Pulse
VP = RS422 Variable Pulse (PWM), Internal/External Interrogation
CP = RS422 Control Pulse
TP = TTL Start/Stop Pulse

0-10 VDC, +/-10 VDC, 0-5 VDC, +/-5 VDC

Max Load Resistance: 500 Ohms

Minimum Load Resistance: 2K Ohm
Output Current: Guaranteed 5mA minimum
Analog Ripple: ≤1 mV maximum
Hysteresis 0.001”
Non-linearity < 0.01% or +/- 0.005”, whichever is greater, (+/- 0.002 Typical)
Storage Temperature e -40° to 221° F
(-40° to 105° C)
Operating Temperature:
Guide Tube

-40° to 185° F (-40° to 85° C)
-40° to 221° F (-40° to 105° C)
Diagnostics Tri-Color LED beside connector/cable exit
NOTE: Specifications subject to change and are based on a typical 48” stroke. *One watt typical at 1ms interrogation time with no recirculations. Faster interrogation times and/or recirculations increase power consumption.

pdfDownload the Model 953 VMAX LDT brochure in *.pdf format.

*** Call, email or live chat today with any questions or to place an order! ***