4 Softstarters | 1SFC132005C0201, rev. M

1SFC132005C0201, rev. M | Softstarters 5

Softstarters

ABB‘s softstarters – The complete range

Softstarters

From the moment the first electric motor was developed,

engineers have tried to come up with ways of avoiding

the electrical and mechanical problems that usually occur

when starting a motor. High inrush currents, current spikes

and excessive mechanical wear are some of the problems

that need to be avoided. One way is to use a Star-Delta

starter. This method is for many applications an insufficient

solution since it handles neither problems with current

spikes or torque peaks nor provides a way to perform a

soft stop. A softstarter on the other hand, will provide far

better performance during the start and allows for soft

stops of the motor.

ABB has been producing softstarters since the beginning of

the 1980’s. Over 30 years’ experience has been incorporated

into the design of today’s product ranges. Modern power

electronics matched with smart circuitry and software gives

users of ABB‘s softstarters, with several state-of-the-art design

features, superior control of current and voltage levels during

motor start and stop.

The solution to both mechanical and electrical problems

AC motors, “the workhorses of the industry”, are used to

drive fans, crushers, agitators, pumps, conveyors and more.

Depending on the motor installation, torque and current peaks

occur. These peaks are everyday reality for production plants

Graphs showing the basic differences between Direct-On-Line starting (DOL), Star-Delta starting and soft starting in terms of the motor voltage (V), motor current (I) and motor torque (T).

V

Motor speed

DOL

Softstart

Star/Delta

T

Torque

Motor current

Softstart

I

Star/Delta

DOL

Motor speed

Motor voltage

Time

100 %

Adjustable

ramp slope

DOL

Star/Delta

Softstart

70 %

58 %

30 %

V

ABB offers four different ranges of softstarters to cover

every customer need for solutions with motor sizes up to

1800 A. This page describes the main characteristics of the

different softstarter ranges.

PSR — The compact range

The PSR softstarter is the most compact of all the softstarter

ranges. A compact softstarter also allows for the design of

compact starting equipment. A PSR together with a MMS

(manual motor starter) makes up a far more compact starting

solution than a Star-Delta starter, for instance.

By including a built-in by-pass the energy losses inside the

softstarter are reduced. And with only three potentiometers,

the setup of the PSR could not be easier. Still, the optimized

ramping characteristics will ensure a very smooth start and

stop for all applications.

PSS — The flexible range

The PSS is the most flexible of the four softstarter ranges from

ABB. It allows both in-line and inside delta connections. As

with the PSR, few settings are needed to get it up and running.

Connecting an external current transformer makes it possible

to activate the current limit function which will allow you to

keep the current at a pre-set level also when starting heavy-

duty applications. The PSS softstarter is the ideal solution

when looking for a robust solid state starting solution where

handling many starts per hour is required.

PSE — The efficient range

The PSE softstarter is the world’s first compact softstarter

with both built-in electronic overload for motor protection

and torque control for excellent control of pumps. A compact

design, packed with functionality, makes the PSE a very

efficient starting solution.

An illuminated, language neutral display and a four button

keypad makes it easy to take advantage of all the advanced

features of the PSE softstarter. The display provides all the

necessary information both during ramping and continuous

operation.

PST(B) — The advanced range

The PST(B) softstarter is the most advanced softstarter in

the range with almost all imaginable functionality included.

Advanced protection of the motor, softstarter and load ensures

a trouble-free operation. Problems are detected before the

motor needs to be stopped thanks to a pre-warning system

that minimizes downtime.

The torque control of the PST(B) was developed in cooperation

with well-known pump manufacturers to ensure the best

possible stop of pumps, without the risk of water hammering

and pressure surges.

With the full-text LCD display in your own language, pre-

programmed application settings and event logging, setup and

operation could not be easier.

By using the ABB‘s FieldBusPlug, you can decide at any time

which bus protocol to use. The fieldbus system will allow you

to setup, control and monitor the softstarter.

all over the world, causing problems in several ways:

arising from Direct-On-Line or Star-Delta starts. The

transients may overload the local supply network and

cause unacceptable voltage variations that interfere with

other electrical equipment connected to the network.

from motor to driven equipment, causing a big need for

service and repair work.

conveyor belts.

when starting and stopping pumps.

The financial consequences of the problems above are

considerable. Every technical problem and every breakdown

costs money in repairs and lost production.

By choosing ABB’s softstarter, all of these problems could

be avoided. Whether the choice is the PSR, PSS, PSE or the

PST(B), ABB’s softstarters all allow smooth start and stops

while keeping mechanical and electrical stresses to a minimum.

PSR

PSS

PSE

PST(B)

• Standard O Optional – Not available

•

–

•

• 1)

Built-in by-pass

1) on PSTB

–

•

–

•

Inside delta connection

–

–

•

O

Coated PCBs

–

–

•

•

Display and keypad

–

–

•

•

Torque control

–

O

•

•

Settable current limit function

–

–

•

•

Electronic motor overload protection

–

–

–

•

PTC input for motor protection

–

–

–

•

Phase imbalance protection

–

–

–

•

Phase reversal protection

–

–

•

•

Locked rotor protection

–

•

•

•

Thyristor overtemperature protection

–

–

•

•

Underload protection

–

–

–

•

Programmable warning functions

–

–

•

•

Analog output

O

–

O

•

FieldBus communication

–

–

O

•

Event log

–

–

O

O

External keypad

PSR18 - 600 - 70

Control supply voltage: 70 = 100-250 V AC

11 = 24 V AC/DC

Operational voltage: 600 V

Current rating: 18 A

Softstarter range