The TM-3100 series digital tachometer can measure speed of a railroad vehicle by using signals from tachometer dynamo equipped on the vehicle. Rotation speed (r/min), kilometers per hour (km/h), kilometers per minute (km/min) can be displayed on the TM-3100.

Adding the TM-0330 analog output card (option) enables voltage/current output of the measured values, and recording them to a data logger etc. The measured data also can be stored to a PC using the TM-0350 RS-232C card (option).

The speed signal from tachometer dynamo has noise content in many cases. The low pass filter setting of the TM-3100 and condenser (set between speed signal output of the tachometer dynamo and the TM-3100) enable noise reduction and stable measurement.