User Guide

Operation 3-7MN850
Motor Starting Definitions
Term Definition
Starting Selectable in Basic Menu as either Keypad or Remote starting method.
Voltage Pedestal Initial voltage applied to motor after the 3 cycle power–up ramp.
Programmed as parameter 11 or as Start Pedestal in Basic Menu.
Kick Pedestal For traction or “frozen” loads, this boost pulse of higher voltage helps the load to start
moving. Kick Start is in the Advanced menu. Kick Pedestal is parameter 13 or as Kick
Pedestal in Advanced menu.
Kick Time Number of cycles duration the kick pedestal voltage is applied. Programmed as parameter
14 or as Kick Time in Advanced menu.
Start Time Number of seconds after the 3 cycle power–up to full motor voltage. Programmed as
parameter 12 or as Start Time in Basic Menu.
Dwell Time Number of seconds that full voltage is applied to the motor before optimizing begins (if
optimizing is selected). Programmed as parameter 15 or as Dwell Time in Advanced menu.
Optimizing Process of detecting underload condition and reducing the RMS voltage to the motor. This
eliminates overflux condition of the motor windings to reduce saturation and results in
substantial power savings (up to 2% efficiency increase). Optimizing is selected by the
keypad or as parameter 7 or as Protection parameter in Basic Menu.
Optimizing Rate A numerical value that represents the rate at which the motor voltage is reduced during
optimizing. When this number is large, improves efficiency on stable loads. A lower
number for unstable loads will reduce speed variations. Programmed as parameter P19.
Contactor Delay A delay is required when an input contactor is energized by the soft–start “Run” relay. This
delay allows bouncing contactor armature to settle during the “Closed” position.
Programmed as parameter 71 or as Contactor Delay in Advanced menu.
3 Cycle Power–up This non adjustable time is to allow voltage build up from zero to the initial pedestal. It is
intended to reduce current inrush and allows for shorted SCR detection. This delay may be
turned off to start a motor even with one shorted SCR or to use high inertia loads on class C
or D motors. Programmed as the “Auto 3MC” parameter in Auto Features menu.
Figure 3-3 Motor Starting Key Terms
Motor
Voltage
Start Time
3 Cycle
Power–up
Kick Pedestal
Kick
Time
Full Voltage
Optimizing
Optimise Rate
Contactor
Delay
Dwell Time Run
Time
Auto Pedestal
Voltage Pedestal