Tachometer Frequently Asked Questions

This explains how to configure the RP-721-120P/R to display the speed in m/min format.

The TM-2100 series (TM-2110, TM-2120, TM-2130, TM-2140) is configured by pulling out the internal components as shown in Figure 2. First, configure the TM2100 series. Connect the power cable and signal lines after configuration.

■Signal cable connection with RP-721-120P/R

Connect using the RP-004 type signal cable (5m) as shown in Figure 1. Longer cables (over 5m) can be manufactured to your specified length.

Figure 1

■TM-2100 Series Tachometer Settings

Refer to Figure 2 below and set values 1 through 4. Further explanations of the settings are provided below. For detailed explanations of the functions, please refer to the instruction manual.
To display "000.0m/min" on the RP-721-120P/R + TM-2100 series, set the multiplier/exponent to "1.0000 × 1/10" and the decimal point to "○○○.○".

Figure 2

• AC-DC settings
  The signal from the RP-721-120P/R is a square wave with a high level of 12V, so set it to "DC". Generally, if the signal is a square wave, set it to "DC", and if it is a sine wave, set it to "AC".
• Voltage input, filter
  Since the RP-721-120P/R signal is a square wave voltage, set "Bit 1: OFF (voltage input side)" and "Bit 2: OFF (filter OFF)". Set "Bits 3 and 4: OFF" (these are unused switches). For open collector signals, set "Bit 1: ON (contact input side)" and "Bit 2: OFF (no filter)". For contact inputs, set "Bit 1: ON (contact input side)" and "Bit 2: ON (filter enabled)" to prevent contact chattering.
• How to find the coefficient (multiplier × exponent)

  

  Set bit 3, bits 3 and 5 to OFF and bit 4 to ON (exponent = 1/10). Also, set bits 6 and 7 to OFF and bit 8 to ON (decimal point ○○○.○). You can set up to 3 decimal places. Set rotary switch 4 to 10000 (multiplier = 1.0000).
• Wide range
  When "Bit 1: ON" is set to 3, it becomes a wide-range setting, and the minimum measurement range starts from 0.1 Hz (0.01 m/min). When stopped, it may take up to approximately 20 seconds for the display to reach 0 in order to determine 0.1 Hz. When "Bit 1: OFF" is set to 1 Hz (0.1 m/min) or higher, and when stopped, the display will reach 0 in approximately 1 second. In this example, "Bit 1: ON" is set. Also, please set "Bit 2: OFF" (this is an unused switch).