AD437153353153en-010301.pdf - 第5页

Con veyor belt – F ood and beverage industries Extend the life of your con veyor belt, and gain the benefit of consistent star t-up r egardless of whether the belt is loaded or not. The sof t starter ensures gentle accel…

Centrifugal pump

– Water

Need to reduce water pressure surges

and mains supply disturbance at start-

up? Then a gentle start

using a soft starter is a good idea.

It also provides a soft stop to control

the effects of fluid hammer often

associated with uncontrolled pump

stop – ultimately extending pump

life and reducing running costs. For

new projects, build these savings in

at design phase – there is no need

to specify pressure surge tanks and

motorized valves to cater for repetitive

high-pressure surges. The minimum

start current function reduces

electrical disturbance on mains supply

and limits demand on supply as well –

reducing reticulation costs for

example in farmland irrigation projects.

The soft starter

• Prevents motor overheating via

integrated protection

• Ensures that pump does not run in

reverse, via start-up protection

• Detects blocked pipes or lack of

fluid via undercurrent protection,

thus preventing unnecessary pump

damage

Centrifugal fan

– HVAC

Extend the life of centrifugal fans

by adding a soft starter – to ensure

gentle acceleration and deceleration,

minimizing wear on coupling, belts,

and bearings.

The soft starter

• Reduces electrical disturbance on the

supply via a minimal start current

• Prevents overheating of motor

windings and body

• Prevents starting when fan direction

is reversed, avoiding damage

• Trips in the event of excess start time,

indicating a jammed or stalled fan,

also providing early indication of

bearing failure

• Detects broken couplings and belts

or clogged fan filter, via and optional

trip or flag for motor undercurrent

To integrate the soft starter directly

with a BMS, the VLT® Soft Starter MCD

600 supports monitoring fan loading,

without the need for extra equipment

an analog output.

Compressor

– Protect your motor

Has the compressor ever locked up,

for instance due to entry of liquid

ammonia? Using a soft starter,

ongoing monitoring prevents damage

to motor, compressor, and couplings in

a lock up situation.

Soft starters provide instant protection

against motor overload, by tripping

the motor immediately.

The soft starter

• Enables load shedding before the soft

starter trips, for compressor overload

or motor overtemperature

• Trips to prevent motor damage

when start-up time exceeds a pre-

programmed limit, for example due

to a jammed or stalled compressor

• Monitors the compressor load using a

0-20 mA/4-20 mA analog output

• Enables optimized compressor

performance with dual speed

dahlander motor control

• Avoids short cycling via restart delay,

promoting longer life of motor,

compressor, and coupling

• Is an easy retrofit for start/delta

starters

Applications

AD437153353153en-010301 > VLT® Soft Starter 4

Conveyor belt – Food and

beverage industries

Extend the life of your conveyor belt,

and gain the benefit of consistent

start-up regardless of whether the

belt is loaded or not. The soft starter

ensures gentle acceleration and

deceleration, reducing risk of product

damage due to jerky starts and sudden

stops. It also protects the couplings,

belts, and bearings against mechanical

wear.

The soft starter

• Prevents conveyor belt slap during

start

• Reduces stress on counter- balances

and weights

• Reduces electrical disturbance on the

supply, via a minimum start current

function

• Provides protection against

accidental running in reverse

• Detects broken couplings or

broken belts, and trips the motor

immediately

• Detects overload, or a jammed

or stalled conveyor, and protects

equipment by tripping the motor

immediately

Crusher and mill

– Mining

Maximise your crusher or mill

throughput by installing a soft starter

at the motor input. The soft starter

allows the motor to operate at its

upper thermal limit, while carefully

monitoring thermal capacity to ensure

motor protection. The crusher can

then safely ride through temporary

product overload situations

The soft starter

• Eliminates the need for special

control equipment, by connecting

motor thermistors directly into the

VLT® Soft Starter MCD 600 thermistor

input

• Extends the life of couplings, belts,

and bearings by gentle start-up,

minimizing torque transients

• Reduces electrical disturbance on the

supply

• Limits the demand on the supply,

especially critical on remote sites

supplied by generator sets

• Prevents damage due to

unintentional running in reverse, by

preventing start when rotation of the

3-phase incoming supply changes

• Detects broken couplings and

broken crusher belts via undercurrent

protection, and trips to prevent

further damage

AD437153353153en-010301 > VLT® Soft Starter

AD437153353153en-010301 > VLT® Soft Starter 6