Mechanical Specification
Trane Adaptive Frequency™ Drive (AFD)
The Trane AFD is a
The AFD is factory mounted on the chiller and ships completely assembled, wired and tested.
Patented Trane AFD control logic is specifically designed to interface with the centrifugal water chiller controls. AFD control adapts to the operating ranges and specific characteristics of the chiller, and chiller efficiency is optimized by coordinating compressor motor speed and compressor inlet guide vane position. Chilled water control and AFD control work together to maintain the chilled water setpoint, improve efficiency and avoid surge. If a surge is detected, AFD surge avoidance logic will make adjustments to move away from and avoid surge at similar conditions in the future.
AFD is capable of operating at an altitude of 3300 feet rated output current. For every 300 feet above 3300 feet, the rated output current will be decreased by 1%.
AFD Design Features
•NEMA 1 ventilated enclosure with a hinged, locking door and door- mounted circuit breaker with shunt trip, is tested to a short circuit withstand rating of 65,000 amps per UL 508. The entire package is UL/CUL listed.
•Digital keypad displays DC bus voltage, drive output motor current; output frequency (Hz); RPM; kW; percent motor torque; and elapsed time. LED’s also display drive status: running, remote, jog, auto, forward, reverse or program.
•One programmable analog output signal,
•Three programmable relay outputs for customer use.
•Simple modular construction.
•The drive is rated for 480/60/3 input power,
•Input displacement power factor will exceed .96 regardless of speed and load.
•Minimum efficiency of 97% at rated load and 60 hertz.
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•Standard DC bus filter choke to limit harmonic distortion.
•All control circuit voltages are physically and electrically isolated from power circuit voltage.
•150% instantaneous torque available for improved surge control.
•Critical frequency avoidance.
•Output
•Restart into a rotating motor.
•AFD can be started without a motor connected.
Chiller Unit Control Features for AFD The chiller unit control panel standard control capabilities provide for the control/configuration interface to, and the retrieval/display of the collaterally additional AFD related data. AFD standard design features controlled through the starter module of UCP2 include:
•Current limited to 100%.
•Auto restart after an interruption of power limited to four starts per hour, 30 seconds between starts.
•Output speed reference signal
•Digital display on UCP2 panel: output speed in hertz, output speed in rpm, fault, amps, input line voltage.
•Motor overload protection.
•Loss of follower signal – in the event of loss of input speed signal the AFD will default to 38 hertz or hold speed based on last reference received.
•Phase loss, reversal, imbalance protection.
•Power loss ride through.
•Overvoltage/undervoltage protection.
•Motor overtemperature protection.
Environmental ratings:
•32°F to 104°F (0°C to 40°F) operating temperature
•Altitude to 3300 feet (1000 m)
•Humidity, 95%
Input Line Reactor Option
Field installed option mounts on the input side of the AFD to reduce harmonic distortion and help meet
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