31
VersiStart i III
To access the graphs or to change which graph is shown, press the
GRAPHS
button.
The graph can also be paused, to allow past performance to be analysed. To pause the graph, press and hold the
GRAPHS
button
for more than 0.5 seconds. To unpause the graph, press the
GRAPHS
button again.
NOTE
The VersiStart i III will not collect data while the graph is paused. When graphing resumes, a small gap will be shown
between the old data and the new data.
8.4
Start, Stop and Reset Commands
The soft starter can be controlled in three ways:
x
using the buttons on the keypad
x
via remote inputs
x
via a serial communication link
The
LOCAL/REMOTE
button controls whether the VersiStart i III will respond to local control (via the keypad) or remote control (via
the remote inputs). The VersiStart i III can also be set to allow local control only or remote control only, using parameter 6A
Local/Remote. The Local LED on the keypad is on when the soft starter is in local control mode and off when the soft starter is in
remote control mode.
The
STOP
button on the keypad is always enabled.
Control via the fieldbus communication network is always enabled in local control mode, and can be enabled or disabled in remote
control mode (parameter 6B Comms in Remote). Control via the serial communication network requires an optional communication
module.
8.4.1
Using the Soft Starter to Control a Motor
To soft start the motor, press the
START
button on the keypad or activate the Start remote input. The motor will start using the start
mode selected in parameter 2A.
To stop the motor, press the
STOP
button on the keypad or activate the Stop remote input. The motor will stop using the stop mode
selected in parameter 2H.
To reset a trip on the soft starter, press the
RESET
button on the keypad or activate the Reset remote input.
To stop the motor with a coast to stop, regardless of the setting of parameter 2H Stop Mode, press the local
STOP
and
RESET
buttons at the same time. The soft starter will remove power from the motor and open the main contactor, and the motor will coast to
stop.
8.5
Soft Start Methods
Soft starters offer a variety of methods to control motor starting. Each soft start method uses a different primary control parameter.
8.5.1
Constant Current
Constant current is the traditional form of soft starting, which raises the current from zero to a specified level and keeps the current
stable at that level until the motor has accelerated.
Constant current starting is ideal for applications where the start current must be kept below a particular level.
Cur
rent (
%
motor
ful
l l
oad c
ur
rent)
700%
600%
500%
300%
100%
400%
200%
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
1
3
2
1: Initial Current (parameter 2C)
2: Current Limit (parameter 2B)
3: Full voltage current
Rotor speed (% full speed)
