Eddy Current Sensors - HE-A

The HE-A Series vibration transducer is an eddy-current transducer designed to satisfy the American Petroleum Institute API Standard 670. It measures the shaft vibration of rotating machinery without contact.

This is the most appropriate sensor to measure the shaft vibration of rotating machinery supported by plain bearings and is frequently used to monitor the vibration of turbine generators and compressors.

In addition, it can be used in an explosive gas atmosphere due to its intrinsic safety construction.



Main Functions 

System composition

Consists of sensor, extension cable and driver. Available in system lengths of 5m and 9m to cover the total distance between sensor and driver.
Intrinsic safety explosion-proof construction RIIS equivalent to IEC standard, Ex ia IIC T6, FM, BASEEFA.
Environment Extensive operating temperature range (-40...+170 0C), not affected by lubricating oil mist or dust (exclude connector), ammonia resistance and measures for hydrogen sulfide-protected models are also available (for details, contact us).
Conforming to API Standard product which is based on API Standard 670 regarding scale factor error, interchangeability and sensor size.

Technical data 



Calibrated material

JIS SCM440 (AISI 4140 Steel) flat surface

Linear range

2,000 mm (approx. 80 mils)

4,500 mm (approx. 180 mils) (less than +/- 75 mm at linearity)

4,000 mm (approx. 160 mils) (less than +/-10 % at scale factor)


787 mV/100 mm (200 mV/mil)

394 mV/100 mm (100 mV/mil)

Scale factor error

Within +/- 5 % of 787 mV/100 mm (if calibrated as a system)

Within +/- 10 % of 394 mV/100 mm (if calibrated as a system)


Winthin +/- 20 mm of 787 mV/100 mm (if calibrated as a system)

Within +/- 75 mm of 394 mV/100 mm (if calibrated as a system)

Operating temperature range

Sensor: -40...+177 0C (-40...+350 0F) (connector: max.. +125 0C)

Extension cable: -40...+177 0C (-40...+350 0F) (connector: max.. +125 0C)

Driver: -38...+80 0C (-36...+176 0F)

Operating humidity range

30...95 % RH (non-condensing, non-submerged)

Power supply

-17.5...-26 VDC

Max. output voltage

Approx. -22 VDC (at -24 VDC power supply voltage)

Current consumption (at 10 kW load resistance)

Max. -16 mA

Max. -20 mA

Frequency response

DC to 20 kHz (-3 dB)

DC to 10 kHz (-3 dB)

Output impedance

50 W

Sensor tip diameter

Approx. f5 mm or f8 mm

Approx. f11 mm

Connector material

Stainless steel, gold-plated finish

Sensor cable length

0.5 m or 1 m

System cable length

Sensor cable length + Extension cable length = 5 m +/- 10 % or 9 m +/- 10 %






Extension Cable