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- MarCal 16 EWR-X - Digital Caliper for special applications, IP 67
- MarCal 16 EWR-AA - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-AI - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-AR - Digital Caliper for special applications, IP 67
- MarCal 16 EWR-BA - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-C - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-H - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-LI - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-NA - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-RW - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-S - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-SA - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-SI - Digital Caliper for special applications, IP 67, Data interface
- MarCal 16 EWR-SM - Digital Caliper for special applications, IP 67, Data interface
- MarCal - Vernier calipers
- MarCal - Dial calipers
- Micromar - Micrometers
- MarTest - Test Indicators and Touch Probes
- MarCator - Digital and Dial Indicators
- MarCator 1075 R / 1086 R / 1087 R / 1088 - Digital indicator
- MarCator 803 / 805 / 810 - Mechanical dial indicators
- MarCator - Mechanical dial indicators ANSI/AGD
- MarCator - Dial indicator, ANSI/AGD Group 0
- MarCator - Dial indicator ANSI/AGD Group 1
- MarCator - Dial indicator ANSI/AGD Group 2
- MarCator - Dial indicator ANSI/AGD Group 3
- MarCator - Dial indicator ANSI/AGD Group 4
- MarCator - Long-range indicators
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- Millimess - Digital and Dial Comparators
- MarStand - Indicator Stands, Comparator Stands, Run out Testing Instruments
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- MarCal - Calipers
- Millimar - Electrical Length Measuring Instruments and Multi-Gaging Metrology
- Millimar - Indication and evaluation instruments
- Millimar - Inductive probe
- Millimar 1301 / 1303 - Inductive probe
- Millimar 1304 K - Inductive probe
- Millimar 1318 - Inductive probe
- Millimar 1340 - Inductive probe
- Millimar P1300 - Inductive probe
- Millimar P2000 - Inductive probe
- Millimar inductive indicator probes - Inductive probe
- Millimar measuring heads with parallel spring-loaded system - Inductive probe
- Millimar - Air gages
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- Digimar - Height Gages
- MarVision - Optical Measuring Instruments
- MarSurf - Mobile Roughness Measuring Units
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- MarSurf - Automatic Roughness and Contour Measuring Systems
- MarSurf - Optical Measuring Units
- MarForm - Table Formtesters
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- Precimar - Gage Block and Dial Gage Testing Unit
- Precimar - Workshop and Setting Units
- Precimar - Universal and High End Length Measuring Units
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- MarOpto - Measuring Devices for Optics Industry
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- MarWin - Software platform
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- MarSolution - Measuring Devices based on Millimar
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The commutator is responsible for the reversal of electrical polarity. It is also called the reversal switch. To safeguard an optimal function, some parameters are of particular importance. Compliance with defined surface roughness ensures good contact between the commutator and the contact brushes while keeping wear at a minimum.
Precise roundness and runout characteristics of the entire disc sets are important parameters. The segment distance can be determined with a formtester as well as with special measuring devices. Testing is required since segment distances that are too large foster the formation of sparks between carbon brushes and commutator, thereby increasing wear. This in turn has a significant influence on the life of the engine.