Schneider Electric 58 TRX User Manual

Class 8839 58M Enclosed AC Drives

Specifications

179

09/2003

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.

2.11 AC 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.