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10 . The VFD shall be relatively insensitive to waveform distortion, especially the waveform <br /> distortion caused by the VFD . <br /> 11 . A six pulse converter section consisting of a three-phase , full wave phase controlled <br /> rectifier or diode bridge converter to convert incoming A . C . power to constant voltage <br /> D . C . <br /> 12 . D . C . bus capacitors and inductors necessary to filter rectification ripple . <br /> 13 . Three-phase full wave inverter to construct an A . C . wave form, with minimum harmonic <br /> content, at any frequency between 0 and 60 Hz. to control motor speed . Motor terminal <br /> voltage shall be controlled in proportion to output frequency such that the voltage to <br /> frequency ratio remains essentially constant . <br /> 14 . Adjustable volts/Hz ratio . <br /> 15 . Adjustable PWM carrier frequency. <br /> 16 . Independent acceleration and deceleration controls , adjustable from 0 to 600 seconds. <br /> 17 . The drive shall accommodate the opening of a disconnect between the drive output and <br /> the motor, while under full load. <br /> 18 . All input/output signals shall be wired to terminal strips for field terminations . Provide <br /> an RS232 or RS485 port for remote computer monitoring. <br /> 19 . Provide panel mounted master reset pushbutton for all safety and overload circuitry. <br /> 20 . Elapsed motor run-time meter with six digit nonreset indicator operable through auxiliary <br /> contacts from the VFD. <br /> 21 . Provide typewritten terminal block schedules and wiring diagrams within a plastic holder <br /> permanently attached to the inside door of the VFD . <br /> 22 . Adjustable current limit to control the maximum controller output current during starting <br /> and running. <br /> 23 . Minimum and maximum speed adjustment. Minimum speed shall be factory set at 50 <br /> percent of motor nameplate rated full load speed. Maximum speed shall be preset to 100 <br /> percent of motor nameplate rated speed or as required by existing motor nameplate full <br /> load current. The drive shall provide at least three adjustable setpoints to lock out <br /> continuous operation at frequencies which may produce mechanical resonance. <br /> 24. The VFD shall be capable of starting into a motor rotating at any speed without tripping. <br /> 25 . Key circuit points shall be monitored by light emitting diodes, (LEDs) to assist in <br /> troubleshooting. Each shall be labeled and referenced to the instruction manual. <br /> 26. The VFD shall be operable with the output open circuited. <br /> i <br /> 044572017 <br /> 16483 -6 <br /> i <br />