Emerson AMPGARD RVSS, Instruction Booklet

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43 EATON
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Instruction Booklet IB020003EN
Effective January 2021
AMPGARD RVSS
Reduced Voltage Soft-Starter
User Manual
Section 7: Functional description
Following are descriptions of the most often used starting and
stopping modes for the AMPGARD RVSS.
7.1 Jog
Jog mode is a selectable control mode that allows for brief and
temporary motor starts. It has its own motor voltage setting, and
will apply that voltage to the motor. It is not a starting sequence and
does not run the motor up to full speed. If left on too long it will trip
the RVSS out on Fault Code 6 - incomplete sequence.
To jog the motor, set the Profile Start Mode to Jog Fwd or Jog Rev
and issue a Start. Issue a Stop to Stop.
7.2 Normal start
Normal start is a start sequence configured by selecting one of the
starting possibilities shown in section
1.5
.
Normal start consists of closing the starter main contactor, enabling
the Power Poles, applying variable voltage to the motor, monitoring
motor acceleration progress, detecting when the motor has reached
the start sequence transition current threshold %, UTSD, and closing
the Bypass contactor and disabling SCR firing.
7.3 Coast stop
Stop is a motor stopping sequence configured by selecting one of
the stop possibilities shown in section 1.6 . Stopping consists of
opening the main and bypass contactors.
7.4 Soft stop
When selected as a stopping option, Soft Stop provides a slow
decrease in output voltage, extending the stopping time of the
motor. Soft Stop is typically used with pumps. Upon Stop, the
Bypass contactor opens and the Soft-Starter truck applies a gradually
reducing ramp of voltage to the motor to control the deceleration.
7.5 Bypass mode
Bypass mode is an RVSS alternative mode that can be employed
when it is necessary to run the motor without the SCR Power Poles
providing variable voltage. By closing the Bypass contactor and
disabling the RVSS control electronics, the upper cell main contactor
can provide FVNR starting, just as it would if the RVSS were a
standard across-the-line starter.
This feature is offered as a temporary measure when the RVSS SCR
control is not available, and is only to be employed if the motor and
its connected load can tolerate the abrupt FVNR starting.
Bypass mode is initiated while the RVSS is stopped by moving
the Bypass Mode selector switch SS2 (located in the starter cell
low voltage compartment) from the Normal position to the Bypass
position. See
Figure 40
.
Figure 40. Bypass selector switch SS2.