Constant Torque Motor

Constant Torque Motor

• Agenda–What is torque

–General Motor Characteristics

–Motor connections

–PSC versus Constant Torque Blower curves

–Troubleshooting

What is Torque

What is Torque

F

r

What is Torque

F

r

Motor

Blower Wheel

Rotational Force

Constant Torque Motors

• General Characteristics

– Same power conversions in the module as variable speed. (Creates 3-phase dc from line voltage)

– Same efficiency as variable speed.

– Permanent magnet rotor same as variable speed

Constant Torque Motors– Control is optimized around

providing constant torque• Does not have the

flexibility of the variable speed. motor.

– Motor receives line voltage all the time – just like variable peed

– Motor is programmed, similar to variable speed

– Soft (controlled) starting – similar to variable speed

– Simpler Interface than variable speed

Constant Torque MotorsMotor Voltage

115 voltsRated 110v-120vMin 98 voltsMax132 volts

230 voltsRated 220v-240vMin 196 voltsMax 264 volts

Normal Hz 50-60 HzMin 47HzMax 126 Hz

RPM 1050Control Input 24vac/dc

Min 12vac/dcMax33vac/dc

Constant Torque Motor

Constant Torque Motor

Note: These motors are NOT dual voltage.

L = Line, G = Ground, N = Neutral

3/16” x 0.020 QC’s

Same nomenclature for 115V and 230V(just treat neutral as L2)

Blank slot for keying/future use.

Hi-Voltage Connections

Constant Torque MotorLow-Voltage Connections

Std. 1/4” x 0.036 QC’s24vac Common

24vac/dc ConnectionsApplying 24vac to a“Tap” tells the motorto produce the torqueprogrammed into thatmemory location.(See next slide)

Constant Torque Motor

Tap 1 32 54

Value 50% 70%60% 80% 90%

24 vac is applied to the Tap in order to tell themotor what torque to produce.

24

PSC Motor

CTM Motors

Constant Torque Motor

PSC Motor Torque “Constant-Torque” Motor Torque

Constant Torque Motor• Troubleshooting – (until further notice)

• Apply Line Voltages

• Apply 24vac/dc signal to Tap 1. This tap should always be programmed

• If it doesn’t start, replace motor module combination

• Applying 24vac/dc to an un-programmed motor or un-programmed torque tap, motor will not start. (Please return for warranty)

Constant Torque Motor

• Labels are expected to have the Taps and their percentages listed on the motor

• Troubleshooting – The Future

• The supplier of the CTM has requested the motor and module combination returned for warranty the first year.

• Separate motor/modules will be available – after the first year

Constant Torque Motor

• Replacement Parts–1st Year – Motor + module will be replaced as

a unit

–Memphis will program the initial replacement motors. (Updated programming boxes are require for field programming.)

– In time, programming will be rolled out to the field, as we currently have with the ECM 2.3, and files will be uploaded to the Amstdnet.

Constant Torque Motor

• More information will be available at the 2006 Technical Conference

Question ?