Problems/malfunctions involving TB-type products

The rotation speed display shows erratic measurements, indicates a speed below the actual speed, or malfunctions from time to time.

Dust may have accumulated on the rotary sensor (disc) in the TB measurement component. Contact your dealer or a nearby sales office.

The torque indication and rotation speed indication are unstable.

Check the alignment of the coupling connecting the shaft of the TB measurement component to the shaft of the test motor. Check for slipping at the coupling.

The calibration results differ for the left and right values.

After excitation, suspend the weight on the calibration bar and check to confirm that the calibration bar is horizontal.

The torque meter shaft won't rotate.

In certain cases, the shaft of the torque meter may not rotate if the starting torque of the test motor is low. Turn the shaft of the torque meter by hand. Also, check to see if the motor is in an excitation state.

I feel resistance when I turn the shaft of the TB measurement component.

Depending on the condition of the instrument when measurements end, some cogging torque may remain due to incomplete removal of magnetism (remanent magnetism) in the brake unit. To remove remanent magnetism, refer to the operating manual or the remanent magnetism degaussing method described on our website.

How to use TB-type products

I hear abnormal noises during measurements.

A worn bearing can cause rattling. If the instrument has seen extended use over many years, it may need to be inspected. Contact your dealer or a nearby sales office.

The load won't stabilize, even under a constant load.

The motor analyzer or TB measurement component may be defective. Contact your dealer or a nearby sales office.

Why does the system indicate a load even when I run the test motor under no load?

The TB-type products use a bearing to support the brake unit. Even if the test motor operates under no load, a small load is imposed by bearing and windage losses.

The CW and CCW values deviate dramatically during torque calibration. Can I make adjustments to address this?

The torque sensor is probably defective. Contact your dealer or a nearby sales office.

The instrument won’t measure voltage or current.

Check the following:

  • Are the motor and power supply correctly connected?
  • Is the analyzer correctly connected to the EVA-1 or WT1600/WT1800 (manufacturer: Yokogawa Electric)?
  • If you're using EVA-1, is Drive set to #2 or higher?
  • If you're using the WT1600/WT1800 (manufacturer: Yokogawa Electric), are the necessary elements enabled?
  • Are the voltage and current ranges properly set?

Our instrument won't take measurements from low-speed geared motors.

For measurements from low-speed geared motors operating in the several hundred revolutions per minute range, we recommend changing the rotary sensor (disc) in the measurement component from the standard 60P/R to a 600P/R. Increasing rotation sensing resolution will allow measurements of low-speed rotation.

I can't measure current or voltage when I try to measure the S-T characteristics and current-voltage characteristics of a single-phase motor using the PC-SAA2/PC-SAA3 motor analyzer.

  1. You may have set the Drive to #1.Select Drive in the Range menu and choose #2.
  2. The current and voltage being measured may exceed the Range settings.Check and set the appropriate range in the Range menu, if necessary.

The software can't communicate with the motor analyzer.

Check the following:

  • Are the PC and motor analyzer correctly connected?
  • Is the COM port of the PC set correctly?
  • The motor analyzer is usually preset to use COM Port 1.
  • Is the communication port set correctly?
  • Is the baud rate of the WT1600/WT1800 (manufacturer: Yokogawa Electric) set to 19,200 bps?
  • Is the software installed properly?