The MHE-7 Series LVIT (Linear Variable Inductance Transducer) Position Sensor from Alliance Sensors Group offers more robust construction and a lower cost of ownership than other embeddable, in-cylinder sensing technologies, making the MHE-7 the preferred choice of cylinder users. These sensors can be embedded into the end cap of industrial or mobile hydraulic cylinders or electric linear actuators and are based on a contactless inductive sensing technology that employs a 7 mm diameter probe with a shorter stroke-to-length ratio than most other sensing technologies. It uses a simple, gun-drilled, blind hole in the cylinder rod to sense the rod's position without requiring any targeting element(s) to be assembled to the piston.
An MHE-7 has a 28 mm (1.10 inch) diameter sensor head with an O-ring and back-up ring in a groove. It can be mounted in an industry standard 28 mm diameter cavity in the cylinder cap and locked in with radial set screws or a snap ring. Being contactless, an MHE-7 Series sensor does not wear out and has no output signal deterioration over the life of the sensor because it uses a simple inductive coil. The MHE-7 sensor can withstand much greater shock and vibration than other technologies. The MHE-7 is also offered with ASG’s proprietary SenSet™ feature whereby a sensor’s analog output can be easily adjusted after installation to match the range of motion of the cylinder rod.
For more information see the technical datasheet below.
- - LVIT Technology™ (Linear Variable Inductance Transducer)
- - Senses the Cylinder Rod Itself
- - Extremely Robust Construction
- - Contactless Sensing for Long Sensor Life
- - Easily Adapts to Existing Cylinder Designs
- - High Resolution with Choice of Several Analog I/Os
- - SenSet™ Feature for Field Scalability of Analog Output
| Analog I/Os: | 0 - 5 V or 0.5 - 4.5 V output, 8 - 30 V input, 35 mA max. 0 - 10 V output, 12 - 30 V input, 35 mA max. 4 - 20 mA, 3-wire sourcing output, 18 - 30 V input, 60 mA max. (75 C max.) |
| Measuring Ranges: | 0-25 mm to 0-900 mm (1 to 36 inches) Full Scale |
| Linearity Error: | ±0.15% of Full Scale Output (FSO) typical, ±0.25% of FSO max. |
| Resolution: | 0.025% of FSO |
| Update Rate: | 300 Hz nominal |
| Operating Temperature: | -20 to 85 C (-40 C to 105 C Extended Range) |
| Temperature Coefficient: | ±0.015% of FS/deg C |
| Operating Pressure: | 5000 psig (350 bar) max operating, 7500 psig (520 bar) proof |
| Vibration: | 5-20 Hz 0.5 inch p-p; 20-2000 Hz 4.2 g p-p |
| Shock: | 1000 g, 11 msec. |
| Terminations: | IEC IP-67 |
| Humidity: | 95% RH, non-condensing |
| Electrical | Probe | Range | Housing |
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| Housing | Bore | Bore |
MHE | X- | X- | XXX- | XX- | XX- | XX- | X | XX- | XX |
| E -Voltage | 7 -7 mm | 025 - 250 | 28 - 28 mm | 00 - 1 m cable | 05 - 0.5-4.5 V | A - Aluminum | 08 - 8 (25-100 ranges) | AL - Aluminum |
| I - Current |
| (25 mm increments) |
| 12 - 12 inch leads | 06 - 4.5 to 0.5 V | S - 300 Series SS | 95 - 9.5 (125-200 ranges) | AS - Alloy Steel |
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| 10 - 0 to 10.0 V |
| 11 - 11 (225-900 ranges) | CS - Carbon Steel |
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| 250 - 500 |
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| 11 - 10.0 to 0 V |
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| SS - Stainless Steel |
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| (50 mm increments) |
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| 20 - 4 to 20 mA |
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| 21 - 20 to 4 mA |
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| 500 - 900 |
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| 50 - 0 to 5.0 V |
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| (100 mm increments) |
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| 51 - 5.0 to 0 V |
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If you are looking for CAD drawings of our MHE-7 sensor, simply call us at 856-727-0250 or use the online contact us form by clicking here.
Download LVIT Linear Position Sensor MHE-7 DatasheetWhat Is the MHE-7 and How Does It Work?
The MHE-7 Series LVIT (Linear Variable Inductance Transducer) from Alliance Sensors Group is an embeddable in-cylinder position sensor designed to mount directly in the end cap of hydraulic cylinders, pneumatic cylinders, and electric linear actuators. Unlike external position sensors that require mounting brackets and rod extensions, the MHE-7 installs inside the cylinder itself — sensing the rod’s position through a simple gun-drilled blind hole with a supplied targeting element assembled to the piston.
The sensor uses a 7 mm diameter inductive probe housed in a 28 mm (1.10 inch) diameter sensor head. The head mounts in an industry-standard 28 mm cavity in the cylinder cap and locks in place with radial set screws or a snap ring. An O-ring and back-up ring in a machined groove provide sealing against the hydraulic medium. With measuring ranges from 25 mm to 900 mm (1 to 36 inches), the MHE-7 covers the full spectrum of industrial and mobile hydraulic cylinder strokes.
Why Choose an In-Cylinder LVIT Over External Position Sensors?
Many in-cylinder sensing technologies require a magnet, encoder strip, or other target element to be assembled to the piston or rod. This adds manufacturing steps, introduces potential failure points inside the cylinder, and complicates piston seal design. The MHE-7 senses the supplied target element within the cylinder rod — the only modification required is a gun-drilled blind hole in the rod, which is a standard machining operation that does not weaken the rod or interfere with seal geometry. This simplicity reduces cylinder manufacturing cost.
How Does In-Cylinder LVIT Sensing Compare to Magnetostrictive Sensors?
Magnetostrictive in-cylinder sensors require a ring magnet assembled to the piston, precise alignment of the sensing waveguide, and careful handling during cylinder assembly to avoid damaging the sensing element. The MHE-7’s inductive sensing approach eliminates all of these requirements — there is no magnet to install, no waveguide to protect, and the robust construction withstands the shock and vibration levels common in industrial and mobile hydraulic service. For cylinder manufacturers and end users evaluating embeddable position sensing options, the MHE-7 provides a lower total cost of ownership with simpler installation and higher mechanical robustness.
Construction and Environmental Performance
Built for Hydraulic Pressure and Harsh Environments
The MHE-7 is rated for 5,000 psig (350 bar) continuous operating pressure with a 7,500 psig (520 bar) proof rating, covering the majority of industrial and mobile hydraulic system pressures. The sensor withstands 1,000 g shock and continuous vibration from 5 to 2,000 Hz, making it suitable for mobile equipment, heavy machinery, and industrial presses where mechanical abuse is a daily operating condition.
Available in aluminum or 300 series stainless steel housings, the MHE-7 can be matched to the cylinder material and operating environment. Stainless steel construction is recommended for subsea, marine, and corrosive environments where aluminum would not provide adequate protection.
Operating Temperature and Sealing
Standard operating temperature covers -20°C to 105°C for mobile equipment exposed to extreme ambient conditions. IP67-rated terminations protect the electrical connection, while the O-ring and back-up ring seal the sensor head against the hydraulic fluid inside the cylinder.
Key Applications for the MHE-7
Hydraulic and Pneumatic Cylinder Position Feedback
The primary application for the MHE-7 is closed-loop position feedback in hydraulic and pneumatic cylinders. By embedding the sensor in the cylinder end cap, the position measurement is fully protected from external damage, contamination, and tampering — eliminating the failure modes that external rod-mounted sensors face in industrial and mobile environments. Cylinder manufacturers integrate the MHE-7 during production, and end users benefit from a position-sensing cylinder that requires no external sensor installation or maintenance.
Mobile Hydraulic Equipment
Construction equipment, agricultural machinery, material handling vehicles, and forestry equipment all use hydraulic cylinders in applications where external sensors would be exposed to impact, debris, and weather. The MHE-7’s in-cylinder mounting eliminates this exposure entirely, providing reliable position data for boom control, blade positioning, steering, and implement height feedback in environments that destroy externally mounted sensors.
Subsea and Marine Actuators
For subsea hydraulic cylinders and marine actuator applications, the MHE-7 in stainless steel construction provides embeddable position sensing that operates under significant hydrostatic pressure. The contactless inductive sensing principle is unaffected by the hydraulic fluid medium, and the absence of internal magnets or delicate waveguides eliminates the failure modes that compromise other in-cylinder sensing technologies in deep-water service.
Electrical Output and System Integration
Analog Output Options for Direct PLC Connection
The MHE-7 provides DC-in/DC-out operation with multiple analog output options: 0–5 V, 0.5–4.5 V, or 0–10 V voltage outputs, and 4–20 mA current output. All outputs connect directly to PLCs, motion controllers, and DAQ systems without external signal conditioning. Reverse-acting outputs (descending voltage or current with extending rod) are available for applications where the control system requires inverted feedback.
SenSet™ Field Programmability
The MHE-7 includes ASG’s SenSet™ feature, allowing the sensor’s analog output to be scaled after installation to match the actual range of motion of the cylinder rod. This eliminates the need for exact stroke-to-sensor-range matching at the time of order, and allows a single sensor model to be used across cylinders with slightly different stroke lengths — simplifying inventory for cylinder manufacturers who build multiple cylinder sizes.
Key Specifications
Measuring ranges: 25 mm to 900 mm (1 to 36 inches) full scale
Linearity error: ±0.15% FSO typical, ±0.25% FSO maximum
Resolution: 0.025% of full-scale output
Update rate: 300 Hz nominal
Operating pressure: 5,000 psig (350 bar) max, 7,500 psig (520 bar) proof
Shock: 1,000 g, 11 msec
Vibration: 5–20 Hz at 0.5 inch p-p; 20–2,000 Hz at 4.2 g p-p
Housing material: aluminum or 300 series stainless steel
Bore material options: aluminum, alloy steel, carbon steel, stainless steel
