Schneider Electric 58 TRX manual Operator Controls, AC Drive Sequencing Requirements, 179

Class 8839 58M Enclosed AC Drives

Specifications

j.The AC Drive shall offer programmable DC injection braking that will brake the AC motor by injecting DC current and creating a stationary magnetic pole in the stator. The level of current will be adjustable between 50- 150% of rated current and available from 0.0- 30 seconds continuously. For continuous operation after 30 seconds, the current shall be automatically reduced to 50% of the nameplate current of the motor.

k.Sequencing logic will coordinate the engage and release thresholds and time delays for the sequencing of the AC Drive output, mechanical actuation and DC injection braking in order to accomplish smooth starting and stopping of a mechanical process.

2.10 OPERATOR CONTROLS

Note to Specifier: Select the operator control strategy that is appropriate for application requirements.

a.Industrial rated 22mm type control operators and pilot devices shall be door mounted and used independently of the keypad display to select operator control modes of [Hand-Off- Auto, Communication-Auto-Off-Hand, Hand- Off-Auto Start Stop, Hand-Off-Auto Local- Remote]. A door mounted manual speed potentiometer shall be used to control speed in the Hand mode of operation.

Control modes shall function as follows:

1.Hand – The Hand mode shall allow manual operation of start, stop and speed control. The AC drive shall start when the control operator is in the Hand mode and run and at low speed setting of the drive or higher as required by the position of the manual speed potentiometer. This mode shall function as 2-wire control and automatically restart after a power outage or auto restart after fault.

2.Off - The Off position of the control operator shall stop the AC drive and prevent it from restarting while in the Off position. This position shall also reset the AC Drive after a fault condition has occurred.

3.Auto - The Automatic mode shall receive an auto start contact rated 115VAC to control start and stop of the AC Drive. This contact shall also start and stop bypass (if used) when both the Automatic mode and Bypass modes of operations are selected. In Automatic mode the user shall remotely reset the AC Drive by opening and closing the Auto-start contact. Speed control shall

be from a customer supplied [4-20mA, 0- 10Vdc] signal.

4.Comm – The communication mode shall allow start, stop and speed control over network communication. (See Communication and Network Requirements.)

5.Start-Stop – Start / Stop pushbuttons shall provide 3-wire start stop control when the drive is in the hand position. The stop push button shall only be active in the Hand mode of operation.

6.Local Remote – Local / Remote selector switch shall provide speed reference control between a manual speed potentiometer and the remote speed reference when in the Auto mode of operation.

b.The AC Drive shall include door-mounted “Power On”, “AFC Run”, “AFC Fault”, “Auto/ Comm” mode and “Bypass” pilot lights. All pilot lights except ‘Power On” shall be Push-to- Test configurations.

2.11AC DRIVE SEQUENCING REQUIREMENTS

Note to Specifier: Specifying a run command relay provides an interface for customer supplied 115Vac safeties and interlocks such as limit switches, flow or temperature switches. This control sequence ensures an AC Drive will stop in any control mode if safeties are opened.

a.All Enclosed AC Drives shall have 115VAC interface and control sequencing. A Run Command Relay (RCR) shall function as a “request to run / run permissive” and close only when all customer wired safeties and control operator conditions calling for run are satisfied. The RCR relay shall prevent drive operation in any operating mode including network communication if the RCR relay conditions are not satisfied. A Drive Run Relay (DRR) shall provide run indication and interfacing to bypass (if used) and other system control sequencing as specified.

09/2003

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