Vacuum Comparators from METTLER TOLEDO
Vacuum Comparators

M_one and M_10 Vacuum Mass Comparators

The Reference in Vacuum Weighing Technology

Vacuum Comparators and Mass Metrology at National Metrology Institutes

METTLER TOLEDO's M_one and M_10 set new standards for mass comparison with the lowest achievable measurement uncertainty. The possibility to dete...

METTLER TOLEDO's M_one and M_10 set new standards for mass comparison with the lowest achievable measurement uncertainty. The possibility to determine measurements at vacuum down to 10–6 mbar ensures that any environment influence is encountered for.

Designed for artefacts of different shape such as Si-spheres, Pt-Ir standards or other cylindrical or knob weights, the M_one is supporting today's and future needs of Metrology Institutes, therefore the M_one is a key component ensuring national traceability of mass and commonly utilized in the redefinition of the kilogram.

The modular design supports a customized system configuration with the possibility to upgrade at later stage.

Products and Specs

M_one ComparatorM_10 Comparator
Article No.On RequestOn Request
OIML Calibration Range E0100 g - 1 kg*1 kg - 10 kg
OIML Calibration Range E1100 g - 1 kg*1 kg - 10 kg
OIML Calibration Range E2100 g - 1 kg*1 kg - 10 kg
OIML Calibration Range F1100 g - 1 kg*1 kg - 10 kg
OIML Calibration Range F2100 g - 1 kg*1 kg - 10 kg
Maximum load1001.5 g10011 g
Readability0.1 μg1.0 μg
Repeatability at nominal load
(5x ABA, measured at)
0.5 μg8.0 μg
Repeatability typical ABA0.3 μg4.0 μg
Electrical weighing range1.5 g11 g
Dial weightsExternalExternal
Linearity (electrical weighing range)2 μg±8 μg
Eccentric load deviation (at test load)0.0 ng (1 g)0.0 ng (10 g)
Settling time30 s30 s
Adjustment built-inMotorizedMotorized
Adjustment with external weight1 g10 g
*Enhance calibration range down to 1 mg by utilizing support weights
Standard Equipment
Weight handlerTurntable, 4 or 6 positionsTurntable, 4 positions
Software and controllerWindows®, standardWindows®, standard
Vacuum chamberRound bell jarRound bell jar
Self centering panIntegratedIntegrated
Weighing panHanging panHanging pan
Separate displayStandardStandard
Admissible Ambient Conditions
Temperature (°C)17 - 2717 - 27
Max. temperature change (°C /12h)0.10.1
Relative humidity (%)45 - 6045 - 60
Comparator (WxDxH, mm)4-Pl.: 274 x 409 x 620
6-Pl.: 344 x 440 x 620
315 x 720 x 850
Display unit (WxDxH, mm)226 x 370 x 155226 x 370 x 155
Comparator weight (kg)300350
Object diameter (D, mm)Cylindrical: 22 - 90
Spherical: 40 - 100
Cylindrical: 18 - 105
Spherical: 18 - 110
Object height (H, mm)100195
Control unit for weight handler (WxDxH, mm)202 x 197 x 92202 x 197 x 92
Vacuum chamber (WxDxH, mm)684 x 884 x 930684 x 884 x 930
Rack for control & display unitOptionalOptional


Product Brochures

Comparator Balances Brochure
Our complete range of vacuum, automated, robotic and manual mass comparators, including volume, density, magnetism, weights, and worldwide service sup...
Brochure : Software Solutions for Mass Calibration
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White Papers

Influences on Mass Calibration ꟷ Minimizing Uncertainties
Learn to minimize measurement uncertainty by controlling or correcting physical influences which affect mass calibration.


Data Sheet : Vacuum Mass Comparators
M_one and M_10 Vacuum Mass Comparators - the Reference for National Measurement Institutes when comparing International and National mass Standards
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Installation Instructions

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