This tachometer is especially designed to operate with our speed
controller so that it can provide easier displaying of motor speed.
· Connect the tachometer in parallel with the tachometer generator (TG).
· If the tachometer (TM) requires longer connection cable, use shielded
twisted pair cable. Don't ground shielding of the cable.
· Accuracy of tachometer readings will depend on variation in motor
performance and operating environment (temperature and noise). The
tachometer should be used as a rough indicator.
Panel cutout drawing
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Calibrate the scale of the tachometer (TM) from the potentiometer on
the rear panel.
1. While running the motor at its full rotation speed without load,
adjust to 1450 min
if power supply is at 50 Hz, or 1750 min
2. Monitor the output signal of the TG on an oscilloscope and
determine the frequency. And adjust:
rotating speed N (min
) = 5 x f (Hz)
Caution: Since the circuit is not isolated from the power supply,
use an insulated tool such as an insulated screwdriver to protect
against electric shock.
External braking resistor (DVOP003)
5.6 Ω 10W
The resistance of DVOP003 is 5.6 Ω. When using commercially available
resistor, choose 4.7-6.8 Ω, 10 W or larger.
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