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  5. BM31 Moisture Indicator

BM31 Moisture Indicator

Quick localisation of near-surface moisture

The BM31 is an electronic moisture indicator by use of which one can quickly and easily detect near-surface moisture in different materials and expeditiously locate moisture distributions in wall, floor and ceiling.

Owing to the dielectric measurement method, moisture indication takes place in an absolutely non-destructive manner, no electrodes or probes have to be inserted into the material to be measured.

The BM31 is not only ready for immediate use, during measurement it also impresses with fast response times and at the push of a button shows the user helpful additional information such as minimum and maximum values in addition to the current real-time measured value on the easily legible back-lit display. Additionally, the momentarily measured value can be recorded via the hold function.

With the BM31 it is not only possible to quickly indicate different near-surface material moisture values, it is also especially suited for the preliminary check of the building materials' readiness for covering for CM measurements.

A few practical benefits:

  • Development, design, production: 100 % Trotec
  • Quick and non-destructive indication of moisture distributions in near-surface areas
  • Useful pre-examination tool for CM measurements
  • Maximum or minimum value and hold function
  • Automatic testing of functions and batteries
  • Ready for immediate use
  • Optimum price-performance-ratio
  • Backlit display
  • Automatic switch-off
  • Practice-optimized German industrial design – protected design patent


BM31 Moisture Meter show in Trotec online shop

BM31 Moisture Meter

The BM31 Moisture meter for fast and non-destructive indication of moisture distribution at areas near to surface (depth of penetration 5 to 40 mm). For ideal localisation of the moisture, this device disposes about a min- and maximum value display, a hold function and an illuminated display.

You save: 36 %

87.33 £ 55.14 £ incl. VAT
Show net price (VAT not included)



Technical data
General information
  Article number 3.510.205.031
Wood moisture [%]
  Min. measuring range [%]
  Max. measuring range [%]
  Resolution [%]
  Accuracy [%]
  Measuring principle
  Min. temperature compensation [%]
  Max. temperature compensation [%]
Material moisture [%]
  Min. measuring range [%]
  Max. measuring range [%]
  Accuracy [%]
  Resolution [%]
  Measuring principle
Material moisture [digits]
  Min. measuring range [Digit] 0
  Accuracy 1
  Resolution [Digit] 1
  Measuring principle Dielectric/capacitive
  Min. penetration depth (non-destructive) [mm] 5
  Max. penetration depth (non-destructive) [mm] 40
  Max. measuring range [Digit] 100
Power supply
  Internal (battery) 1 x 9 V block battery
Device control
  Push buttons
Surrounding conditions
  Operation - min. temperature [°C] 0
  Operation - max. temperature [°C] 50
  Operation – min. relative humidity [% RH]
  Operation - max. relative humidity [% RH] 80
Housing design
  Length (packaging excluded) [mm] 180
  Width (packaging excluded) [mm] 35
  Height (packaging excluded) [mm] 45
  (packaging excluded) [kg] 0.18
Standard scope of delivery
Standard scope of delivery
  Measuring device
  Operating manual
  Protective cap
  Electrode tips (1.5 x 20 mm)
  Electrode tips (2.2 x 8 mm)
  2x union nuts
  Wood type directory
  Factory test certificate
Ascertainable measured values and functions
Internal sensors
  Material moisture [digits]
  Wood moisture [%]
  Material moisture [%]
Functions and features
  Minimum value display
  Maximum value display
  Hold function
  Automatic switch-off
  Non-destructive measurement method
  Backlit display
  Acoustic alarm function
  Selection sensor characteristic map (sens)
  Unit 2
  Selection of wood material characteristics (Mat)
  Temperature compensation
  Manual temperature setting
  Automatic functional test
  Automatic battery test
  Mode selection slide control
  Retaining clip

 standard equipment

 optionally available

 not available


Alternative products

BM31 with alternative products:

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BM12 Moisture Meter show in Trotec online shop

BM12 Moisture Meter

Besides the building and wood moisture the BM12 Moisture Meter determines the ambient temperature, which can be read off optionally °C or °F.

You save: 30 %

11.91 £ 8.23 £ incl. VAT
Show net price (VAT not included)


T510 Moisture Meter show in Trotec online shop

T510 Moisture Meter

The T510 is a professional hand-held measuring device for the exact determination of wood and material moisture content according to the resistance measuring method.

180.59 £ incl. VAT
Show net price (VAT not included)


T610 Moisture Meter, Microwave show in Trotec online shop

T610 Moisture Meter, Microwave

Thanks to the microwave method it is possible to determine moisture up to a depth of 300 mm using the T610 material moisture measuring device. You can achieve extremely accurate and conclusive results with this measuring device when grid measurements are carried out, for example.

574.60 £ incl. VAT
Show net price (VAT not included)


T660 Moisture Meter show in Trotec online shop

T660 Moisture Meter

The T660 moisture measuring device allows the user to detect moisture in brickwork, walls and even campers and RVs using non-destructive technology. The device penetrates materials up to a depth of 4 cm and provides the user with precise information regarding moisture content and distribution.

186.07 £ incl. VAT
Show net price (VAT not included)