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Belt Tension Meter - Type 4

The Type 4 Acoustic Belt Meter  is suitable for measuring tension in all types of power transmission belts, ranging from toothed timing belts, poly-vee belts, and simple vee belts.  The frequency measurement range is from 30Hz to 600Hz which covers most automotive applications.  The Acoustic sensor uses a CLAVIS patented technique for detecting the belt vibration signal whilst minimising ambient noise.  The ‘jaws’ of the sensor should be positioned over the centre of the belt and placed mid length of the belt span.  The sensor should not be allowed to touch the belt as this will reduce the belt vibration signal.  A range of sensors is available to suit belts of differing widths.

The Type 4 Optical Belt Meter  has a frequency measurement range of 10Hz to 600Hz and uses an Optical Sensor Head.  This meter is useful where there is also a requirement to measure tension in a variety of belts, some vibrating at low frequencies.  The Optical sensor head uses an invisible infrared beam to detect vibrations of the belt.  A narrow angle orange LED generated beam is provided to guide the aiming of the sensor.  The very best signal from the belt is seen when the sensor is held perpendicular to the belt at the centre of the span at 9.5 mm (3/8 in) distance.

In most applications the meter is used to make comparative tension checks.  Often two or three spans may be available on which to take measurements.  As the frequency depends upon the span length, the span to be used for measurement must be defined.  Normally it is found that the longer spans are easier to vibrate than the very short span lengths.  If the belt tension adjuster is on the measurement span, ensure that the variation in span length created by the adjuster will not be significant.

This belt meter is operated by a simple ON/OFF keypad button.

A general purpose head is supplied.  A range of interchangeable sensing heads with differing dimensions is available upon request.  For more information about our sensor heads please click here.

Every CLAVIS meter is supplied with a precision mechanical resonator (tuning fork) for simple calibration validation by the user.  If you have additional calibration requirements CLAVIS can supply a Sonic Calibration Meter.  Read more about calibration...

You can expect each device to have the following;

  • CLAVIS Patented Sensor
  • Carrying Case
  • Tuning Fork (Checking Calibration)
  • Calibration Certification
  • Battery Charger
  • Rechargeable Batteries

Technical Specifications

Measurement Range
Frequency Range (Acoustic) 30 to 600Hz
Frequency Range (Optical) 10 to 600Hz
Measurement Accuracy
Below 100Hz +/- 1 significant digit
Above 100Hz +/- 1%
Environment Conditions
Operating Temperature +10℃ to +50℃
+50℉ to +122℉
Shipment & Storage Temperature +5℃ to +70℃
+23℉ to +158℉
Protection Class IP54
Sensor (Optical)
Type Infrared Optical
IR Wavelength 970mm
Visible Aiming Beam Narrow angle orange LED
Housing Machined aluminium
Cable length 1m
Sensor (Acoustic)
Type Type 3 Standard
Belt Size Belts up to 25mm wide
Entry Rear / Top
Housing Casted aluminium
Power Supply
Battery Type AA (1.5V) Alkaline only
Number 4
Expected life 20 hrs
Compartment Location Back of meter
Optional Rechargeable Batteries
Battery Type AA (1300 mAh minimum)
Charger 12 to 15 V DC output
Socket/polarity 3.5mm positive centre
Physical Measurements
Height 185mm
Width 100mm
Depth (Top) 45mm
Depth (Bottom) 36mm


Enquiry Form

Thank you for your interest in CLAVIS.  Please use this form if you have any questions about our products and we'll get back to as soon as we can, or call us on + 44 (191) 262 7869.

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