Powerware ST-2400S user manual

positive and negative torque to the unit) and verify that the torque reading returns closely to the same value. A failure here indicates a likely problem with the dynamometer. Have the dynamometer checked by your dealer or dyno service person.

1.3Make sure that the load has been completely removed from the load cell. Disconnect the load cell from the torque arm of the dynamometer by removing the coupling fastener. If this does not correct the excessive zero offset a likely defective or damaged load cell is indicated. You should have the load cell checked by your dealer or dyno service person.

1.4Make sure that the shunt resistor switch is set to the OFF position.

2.TORQUE SPAN CALIBRATION cannot proceed. This problem occurs when the torque reading is not sufficiently close to that expected from the CALIBRATION TORQUE value. Check the following:

2.1Check to be sure that the CALIBRATION TORQUE is the value expected by the 2400S horsepower computer. The expected calibration torque value is normally programmed into the 2400S by your dealer to match the calibration value and method you will be using to check and adjust the calibration of your unit. You can check this by setting the calibration mode switch back to the OFF position while leaving the CALIBRATION TORQUE applied to the unit. The TORQUE display will now read the (approximate) torque you have applied. If this value is within about +/- 10% of the CALIBRATION TORQUE that you have applied, then it is likely that the value expected by the 2400S for the CALIBRATION TORQUE is different than the value you are using. Check with your dealer or dyno service person to determine the calibration torque you should be using or use the 2400S calibration setup software to re-program the 2400S to expect the calibration torque you are currently using.

2.2If the TORQUE display does not read (within +/- abut 10%) the torque that you have applied a possible defective or damaged load cell is indicated and may need to be repaired or replaced. Have your dealer or dyno service person assist you.

Torque Calibration Notes:

There are several methods which can be used to apply a calibration torque value to the 2400S horsepower computer.

1.) Dead Weight Test Fixture: This method uses a Torque Test Bar (dead weight test fixture) and one or more calibration weights. The torque test bar is attached to the torque arm of the dynamometer, being careful to align the position of the mark on the torque test bar with corresponding mark on the torque arm of the dynamometer. Then connect the test weight(s) onto the torque test bar at the indicated position, usually the 4 foot (1.210 meter) position. The torque produced by the torque test bar must be accurately known, the total weight of the test weights must be accurately known, and the horizontal distance from the center line of the dyno to the indicated position must be accurately known. If any of these three factors is not accurate, then the resulting calibration will not be accurate –and the result is in-accurate torque and power readings from the

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