Zener SMARTSTART 6000 Series, Руководство пользователя

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Introduction
Technical Manual: Smartstart
®
6000 IMI0042 rev D
Page 3
Smartstart
®
6000
Basic Soft Starter Operation
The Zener Smartstart
®
is a reduced voltage controller
designed for starting standard 3 Phase induction motors.
The unit is solid state, using a microprocessor to control
inverse parallel (back to back) pairs of SCR’s.
An SCR/thyrisor is a semiconductor device that latches
when triggered. Once triggered it allows current to flow
in one direction only and turns off at zero current.
The firing angle of the SCR’s are controlled to achieve
the desired acceleration of the motor.
Soft Starters provide the following benefits:
1. Reduced stresses and wear on the mechanics
of the system
2. Reduced starting currents
3. Minimise voltage dips on the supply
4. Lowered Peak demand charges
5. Eliminate belt slippage on fans
6. Smooth acceleration of motor / load
Zener ‘SMART-TORQ
®
’ Torque Control
Feature
The Zener Smartstart
®
6000 incorporates a closed loop
torque control system to provide better control over
starting & stopping 3 phase induction motors.
Conventional voltage ramp control systems typically
produce low torque at low speeds. When starting &
stopping variable torque loads (e.g Pumps) this can
results in a very rapid acceleration or deceleration with a
non linear change in motor speed.
The Smarstart
®
6000 series overcomes these issues by
regulating the torque in the motor to match the load
type during the acceleration & deceleration. This
essentially allows a constant torque to be produced in
the motor. The continual monitoring of the motor
characteristics during the ramp also allows
instantaneous adjustment of the starter output to allow
for changes in load conditions.
The ‘SMART-TORQ
®
’ control system provides smooth
starting & stopping, allowing ramp profiling to produce a
linear acceleration and deceleration of the motor speed.
There are many benefits with variable torque loads such
a pumps and fans by achieving a linear ramp profile and
greater control over deceleration. With pump
applications this provides better control to minimise
water hammer problems.
SMART-TORQ Benefits include:
1. A true linear acceleration of the load and motor
for all load types.
2. Reduced peak inrush starting currents.
3. Reduced stresses and wear on the mechanics of
the system
4. Ramp profiling to better match type of load such
as variable torque loads. Better control of
pumps and fans, without rapid initial ramp but
linear ramp.
5. Reduced heating in motor at low speeds.
6. No instability due to changing power factor.
Closed loop system to monitor and react to
changing power factor.
7. No instability due to slot ripple in 3 wire and 6
wire operation.
8. Better control of deceleration through closed
loop torque control system.
The Smartstart
®
also offers user access to ramp profiling
parameters to fine tune the Torque Control System to
achieve more application specific performance
requirements. See Page 34 for more information.