Tachometer Frequently Asked Questions

TM-3100 Series Digital Tachometer Installation Manual (Short Version) (PDF 1.2 MB)

Due to its high sensitivity, the TM-3100 may be affected by high-frequency noise on the signal line, causing fluctuations in rotation speed. Please be sure to implement the noise reduction measures described in the instruction manual.

Furthermore, if you wish to make the device EMC compliant, please download the "TM3100 Installation Manual" and be sure to follow the instructions to house the device in a metal enclosure, install line filters and surge suppressors on the power wiring, and process the signal shielding wires accordingly.

■ Noise-suppressing wiring

• The GND (Ground) terminal on the TM-3100's power supply must be properly grounded.

  Grounding: Type 3 or higher (100Ω or less), soft copper wire (AWG14) of 2 mm² or larger, maximum grounding extension 20 m

• The shields of all input and output signal cables should be connected to a stable ground at both ends.

• Please refer to the following diagram and keep the signal cables as short as possible.

• The negative wire of the surge suppressor should be no more than 50 cm long.

  

  Part name	Manufacturer name	Model name	Quantity
  Line filter	TDK Corporation	ZHC2203-11	1
  Surge killer	Phoenix Contact Co., Ltd.	F-MS 12ST	1
  Surge killer	Phoenix Contact Co., Ltd.	VAL-MS 230ST	2
  Base for surge killer	Phoenix Contact Co., Ltd.	VAL-MS-BE	1

• Referring to the following diagram, please ground the shield to earth using grounding. We recommend using the EMT series grounding clamp manufactured by Takeuchi Kogyo. If the optional EXTERNAL unit TM-0350 (RS-232C+GATE) is installed in slot B, the RS232C cable should be grounded within 10cm of the TM3100 series digital tachometer; grounding to the personal computer is not necessary.

  

• If the optional DC power supply unit TM-0301 is installed in the POWER slot of the TM-3100, connect the cables to the DC power module located in the POWER slot, referring to the following diagram. At this time, be sure to use a ferrite core manufactured by Seiwa Electric (E04SR301334), and always turn the cable twice around the ferrite core.