MST Digital Soft Starter
MST Digital Soft Starter
MST Digital
Soft Starter
From the moment the first electrical motors were developed,
engineers have been searching for ways to avoid electrical and
mechanical stress caused by the starting and stopping of motors.
Problems with direct-on-line (DOL) starting include high inrush
current, voltage spikes, and excessive mechanical wear that can
occur when motors start and stop. One traditional way to avoid
this is to use a wye (aka “star”) delta starter, but this method is
in many applications insufficient, as problems with current spikes
and torque peaks remain. It also does not provide any way to
perform a soft stop. The MST Digital Soft Starter, on the other
hand, will provide far better performance during a start, as well as
during a stop.
The results are:
• Overloaded lines and unacceptable voltage variation due to
voltage and current transients from DOL and wye-delta starts.
These transients can interfere with other equipment connected
to the power system, from dimming of lights to computer failure
Baldor has been producing soft starters for over 25 years. All of
the experience we have gained has been combined with today’s
digital technology and incorporated into the MST Digital Soft
Starter. Matching modern power electronics with smart circuitry
and software, the Baldor MST Soft Starter offers superior control
of current and voltage during motor start and stop. It also offers
many new features that were unheard of in previous generations.
• For pump systems, water hammer and pressure surges put
excessive loading in pipelines from starting and stopping the
pumps
The Mechanical & Electrical Solution
AC motors are the workhorse of industry. They are used for
countless applications, including fans, crushers, agitators, pumps,
and conveyors to name a few. Too often, unnecessary and
unwanted torque and current spikes are an everyday occurrence
in production plants all over the world, damaging electrical
equipment and causing unnecessary wear on mechanical
systems.
An economical and simple solution is to install a Baldor MST
Digital Soft Starter. The Baldor MST Soft Starter provides smooth
starting and stopping that minimizes mechanical and electrical
stress on your equipment.
Motor voltage
100%
DOL
• Excessive mechanical wear across the entire drive chain, from
motor to driven equipment, causing an increase in service and
repair and causing unwanted down time
• Operational problems, such as damage to products conveyed
from station to station
The financial consequences are considerable. Every technical
problem and every breakdown costs money to diagnose and
repair, not to mention the loss in production.
Motor current
wye/delta
wye/delta
Softstart
Torque
DOL
DOL
wye/delta
70%
Softstart
58%
Softstart
Adjustable
ramp slope
30%
Time
(1) The MST soft starter provides a more gradual
acceleration.
Motor speed
(2) It lowers starting current and eliminates
spikes.
The MST Soft Starter compared to direct-on-line (DOL) and wye-delta (aka “star-delta”)
2
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Motor speed
(3) The MST soft starter eliminates sudden
and damaging changes in motor torque.
The MST Digital Soft Starter provides an advanced set of features
including advanced protections, torque control, programmability
and interface.
Advanced protections for not only the motor, but also the soft
starter and the load ensure trouble-free operation. Pre-warnings
detect problems before the motor needs to be stopped, which
avoids unnecessary downtime.
The torque control function was developed and tested in
collaboration with pump manufacturers to ensure the best
possible stop without water hammer and pressure surges.
The full text LCD display shows what’s happening in plain English
or other language. Preprogrammed application settings provide for
fast and efficient setup. Fault logging assists with troubleshooting
and diagnostics.
Other advanced features include:
• Built-in bypass (370A and above)
• Display and keypad
• Adjustable current limit
• Electronic motor overload protection
• Thermistor (PTC) input for motor protection
• Phase imbalance protection
• Phase reversal protection
• Locked rotor protection
• Thyristor (SCR) overtemperature protection
• Underload protection
• Programmable warning functions
• Analog output
• Event logger
• External keypad option
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MST Digital
Soft Starter
The Advanced Solution
3
Pumps
MST Digital
Soft Starter
Water is the world’s most important resource and water facilities can be found all over the world. Examples of water applications are
freshwater and wastewater systems, circulating water for heating or cooling and irrigation.
Wastewater transportation
• Influent and effluent pumps
• Treatment pumps and fans
Industrial use
• Process feed-water pumps
• District heating pumps
• Cooling water pumps
• Slurry pumps
Drinking water distribution
• Distribution pumps
• Booster pumps
Irrigation
• Intake pumps
• Distribution pumps
Water transmission
• Transfer pumps
• Distribution pumps
• Booster pumps
Desalination
• Intake pumps
• Brine pumps
• Booster pumps
• High pressure pumps
• Drinking water pumps
Water treatment
• Treatment pumps
Effluent water
• Effluent pumps
Raw water intake
• Raw water intake pumps
Effluent water
• Effluent pumps
Raw water supply
• Feed-water pump
Waste incineration
• Effluent pumps
• Fans
• Conveyors
Pumps:
Q How are voltage drops avoided while starting?
A Baldor MST Soft Starters will reduce the starting current, thus
avoiding the voltage drop
Q How is water hammer avoided while stopping?
A Baldor MST Soft Starters use an optimized stop ramp and
control motor torque to eliminate water hammer
Q How does the MST Soft Starter protect the equipment?
A Baldor MST Soft Starters are equipped with specially designed
protection algorithms to monitor overload, underload, and
locked rotor conditions
4
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Fans
Fans:
Q How are extended voltage drops avoided during long starting
times?
A Baldor MST Soft Starters are equipped with current limit to
keep control of the starting current
MST Digital
Soft Starter
Applications
Q How is the life of the driving belts extended?
A The Baldor MST Soft Starters reduce the mechanical stress
during start, thus avoiding belt slippage
Q How is the operation of the fan improved?
A A Baldor MST Soft Starter with underload protection will detect
a broken belt immediately and alert the operator to the problem
Compressors:
Q How is compressor life extended?
A Using a Baldor MST Soft Starter for starting will reduce the
accelerating torque, thereby minimizing the mechanical stress
Compressors
Q How is the compactness of the compressor enhanced?
A Using a compact Baldor MST Soft Starter will reduce the size of
starting equipment over a typical wye delta starter
Conveyors:
Q How is service and repair of the conveyor belt or chain
reduced?
A A Baldor MST Soft Starter will cause minimal mechanical stress
on the conveyor belt
Q How do you avoid running the conveyor belt in the wrong
direction?
A Use a Baldor MST Soft Starter with phase reversal protection
Conveyors
Q How is efficiency of the conveyor belt improved?
A Using the Baldor MST Soft Starter with high and low current
warnings allows you to adjust the load of the conveyor belt for
optimal efficiency
Q How is starting ensured even when there is high starting
resistance?
A A Baldor MST Soft Starter with kick start function will provide
sufficient torque to be able to overcome the initial high friction
from, for example, a temporarily jammed belt
Q How often do fast starting conveyors cause material spillage or
pileup?
A Use Baldor MST Soft Starter to softly accelerate material
handling conveyors
www.baldor.com
5
MST Digital Soft Starter
MST Digital
Soft Starter
Description
MST Digital Soft Starter
Baldor continues a proud tradition of offering the very latest in
motor control technology by introducing the MST digital soft
starter with six SCR three phase voltage control.
Torque Control
The torque control function was developed and tested in
collaboration with pump manufacturers to ensure the best
possible stop without water hammer and pressure surges.
Bypass for Energy Savings
Bypassing the soft starter after reaching full voltage saves energy
and reduces heat. The MST soft starters are equipped with extra
terminals making the connection to an external bypass contactor
easy, while allowing all protections to be active during bypass. Soft
starters starting at 370 Amps have a built-in bypass contactor,
ensuring a compact solution that simplifies installation.
Advanced Protections
The MST soft starters are equipped with almost all protections
imaginable for protecting the motor, the soft starter and the
application. To offer more flexibility, protections can be tailored to
specific needs.
Features
•Wide range of operational voltage 208 – 575 V AC
•Rated operational current 30 to 1040 A
•Full text display and 4 button keypad for easy setup and
operation
•Optional external keypad, IP66 (indoor)
•Built-in bypass contactor (from 370 A) for energy savings and
reduced cooling needs
•Ready for external bypass (30 – 300 A)
•Torque Control for excellent control of pumps
•Current limit, adjustable between 1.5 – 7 x Ie
•Dual motor overload protection with NEMA Class 10 and
Class 30
•Adaptable motor underload protection to detect pumps running
dry or broken belt
•Adaptable locked rotor protection
•PTC thermistor protection to protect the motor from overheating
•Adjustable kick-start to start jammed pumps or conveyors
•Programmable output Form C relays
•Programmable pre-warning functions
•Event log with time stamp
•Analog output showing current, voltage, power factor etc.
0 – 10 V, 0 – 20 mA, 4 – 20 mA
6
Flexible Analog Output
The analog output terminals can be connected to an analog
current meter to show the current during operation, eliminating
the need for an additional current transformer. The analog output
can also be used as an analog input to a PLC or indicating/
metering device.
Display and keypad
The MST soft starter is equipped with a full text display showing
all information in clear text in English or many other languages.
To make it even easier to set up, there are standard settings for
many common applications such as a centrifugal pump, which
will automatically configure the required settings including torque
control when stopping.
External keypad
As an option, the MST soft starter can be equipped with an
external keypad for easy setup and monitoring of the unit without
opening the enclosure door. The keypad can also be used to copy
parameters between different soft starters.
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MST Digital Soft Starter
Description
2 programmable inputs
The MST Soft Starter can be selected according to the rated
motor power in normal duty for applications such as pumps,
compressors, elevators, escalators, short conveyor belts and bow
thrusters. Use heavy duty for applications such as centrifugal fans,
crushers, mixers, mills, stirrers and long conveyor belts.
3 programmable output
signal relays
MST Digital
Soft Starter
Screw mounting
Built-in bypass on 370
Amp units and over
All data available on the front
Analog output or PTC input
Keypad and Display
Green “Power On” LED
Red “Fault” LED
Yellow “Protection” LED
Full text display
User friendly keypad
Preset application settings
External keypad has same design as the fixed keypad
Enclosed Starter
Baldor enclosed combination starters have open starters mounted
and wired in NEMA 12/4 packages. Each combination starter
includes:
• bypass contactor for increased efficiency
• circuit breaker with door-mounted disconnect handle
• 2-wire control circuit
• space heater
• shunt trip
• Hand/Auto/Off selector switch
• indicator lights
Combination starters are available in Class 10 and Class 30 motor
overload protection. Also available in a severe duty rating with
manually energized bypass for emergency direct on line (DOL)
starting.
www.baldor.com
7
MST Digital Soft Starter
MST Digital
Soft Starter
Open Starters - Overview
MST-030-CA ... MST-072-CA
MST-085-CA ... MST-142-CA
Soft Starter. Type
Normal start
Dimensions
(h x w x d)
MST-030-CA
MST-037-CA
MST-044-CA
MST-050-CA
MST-072-CA
MST-085-CA
MST-105-CA
MST-142-CA
Horsepower (460V)
20
25
30
40
50
60
75
100
UL Amps
28
34
42
54
68
80
104
130
Kilowatt (400 V)
15
18.5
22
25
37
45
55
75
IEC Amps
30
37
44
50
72
85
105
142
Max Power Loss (W)
100
120
140
160
230
270
325
435
with bypass (W)
10
11
14
14
17
31
35
37
Inches
10.2 x 6.3 x 7.7
15.4 x 7.3 x 10.6
Millimeters
260 x 160 x 196
390 x 186 x 270
11 lb (5 kg)
29 lb (13 kg)
Weight
Using MCCB only, type 1 coordination will be achieved
MCCB (10 kA, 480 - 600 V, 40 C)
Using J fuses, type 11) coordination will be achieved
J type fuse protection (85 kA)
1)
Ts3
45 A
50 A
Fusible disconnect switch for the above J fuses
Fusible disconnect switch
Line contactors are not required for the soft starter itself
but often used to open if the Overload trips
Line contactor
Overload protection is used to protect the motor from
over heating
Electronic overload relay
Bypass contactors will reduce the power loss of the soft
starter. All soft starters can be operated without bypass
Bypass contactor
70 A
OS60
T4
90 A
110 A
OS100
AF30
125 A
175 A
OS200
AF50
AF75
AF95
OS400
AF110
AF145
AF75
AF110
Built-in
AF16
AF26
AF30
AF50
1) In the event of short circuit Type 1 coordination assures no discharged part beyond the enclosure with soft starter, overload (and contacter) and internal parts damage is acceptable and may occur
8
225 A
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MST Digital Soft Starter
MST Digital
Soft Starter
Open Starters - Overview
MST-175-CA ... MST-300-CA
MST-370 ... MST-470
MST-570-CA ... MST-1050-CA
Soft Starter. Type
Normal start
Dimensions
(h x w x d)
MST-175-CA
MST-210-CA
MST-250-CA
MST-300-CA
MST-370-CA
MST-470-CA
MST-570-CA
MST-720-CA
MST-840-CA
MST-1050-CA
Horsepower (460V)
125
150
200
250
300
400
500
600
700
900
1062
UL Amps
156
192
248
302
361
480
590
720
840
Kilowatt (400 V)
90
110.0
132
160
200
250
315
400
450
560
IEC Amps
175
210
250
300
370
470
570
720
840
1050
Max Power Loss (W)
540
645
765
920
-
-
-
-
-
-
with bypass (W)
62
67
67
90
90
110
105
110
170
170
Inches
Millimeters
Weight
16.5 x 14.2 x 10.6
18.1 x 14.4 x 14.2
20.3 x 17.2 x 15.0
420 x 360 x 270
460 x 366 x 361
515 x 436 x 381
51 lb (23 kg)
68 lb (31 kg)
132 lb (60 kg)
Using MCCB only, type 1 coordination
will be achieved
MCCB (18 kA, 480 - 600 V, 40 C)
Type J or L fuses, type 1 coordination
will be achieved
J or L type fuse protection (85 kA)
Fusible disconnect switch for the above
J fuses
Fusible disconnect switch
Line contactors are not required for the
soft starter itself but often used to open
if the Overload trips
Line contactor
Overload protection is used to protect
the motor from over heating
Electronic overload relay
Bypass contactors will reduce the power
loss of the soft starter. All soft starters
can be operated without bypass
Bypass contactor
T4
MCCB (30 kA, 480 - 600 V, 40 C)
T5
250 A
300 A
400 A
500 A
OS400
AF185
AF210
600 A
AF300
T7
800 A
OS600
AF260
MCCB (42 kA, 480 - 600 V, 40 C)
T6
1000 A
OS800
AF400
1200 A
OS1200
AF580
AF750
T8
1400 A
1800 A
-
-
AF1350
AF1650
Built-in
AF145
AF185
AF210
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Built-in
9
MST Digital Soft Starter – Open
MST Digital
Soft Starter
Ratings: Normal Starting – Class 10
Normal Starting - Class 10
Agitator
Axial blower
Axial Fan
Band Saw
Centrifugal Pump
Chiller
Escalator
Low Inertia Fan
Propeller Fan
Small Pump
Large Pump
Circular Saw
Conveyor, Screw Feeder
Drill Press
NOTE: If more than 10 starts per hour, select one size larger than the standard selection
MOTOR APPLICATION HORSEPOWER
Normal Starting
Class 10 - 400% torque for 30 seconds
208V
230V
460V
575V
7.5
10
20
25
10
10
25
30
10
15
30
40
15
20
40
50
20
25
50
60
25
30
60
75
30
40
75
100
40
50
100
125
50
60
125
150
60
75
150
200
75
100
200
250
100
100
250
300
125
150
300
350
150
200
400
500
200
250
500
600
250
300
600
700
300
350
700
800
400
450
900
1000
Soft Starter
UL
Amps
IEC
Amps
Catalog
Number
Size
28
34
42
54
68
80
104
130
156
192
248
302
361
480
590
720
840
1062
30
37
44
50
72
85
105
142
175
210
250
300
370
470
570
720
840
1050
MST-030-CA
MST-037-CA
MST-044-CA
MST-050-CA
MST-072-CA
MST-085-CA
MST-105-CA
MST-142-CA
MST-175-CA
MST-210-CA
MST-250-CA
MST-300-CA
MST-370-CA
MST-470-CA
MST-570-CA
MST-720-CA
MST-840-CA
MST-1050-CA
A
A
A
A
A
B
B
B
C
C
C
C
D
D
E
E
E
E
Prosoft Sizing Software
These tables can be used to quickly select a suitable soft starter
for most applications. If a more precise selection is required, or for
diverse applications such as extreme heavy duty, use the Baldor
Prosoft selection tool, available from www.Baldor.com.
10
www.baldor.com
MST Digital Soft Starter – Open
Heavy Starting - Class 30
Centrifugal Blower
Centrifugal Fan
Chipper
Disintegrator
Loaded Centrifuge
Loaded Screw Compressor
Loaded Reciprocating Compressor
Pulverizer
Rock Crusher
Separator
MST Digital
Soft Starter
Ratings: Heavy Starting – Class 30
Loaded Mixer
Elevator
Positive Displacement Pump
Reciprocating Compressor
Vibrating Screen
NOTE: If more than 10 starts per hour, select one size larger than the standard selection
MOTOR APPLICATION HORSEPOWER
Heavy Starting
Class 30 - 350% torque for 60 seconds
208V
230V
460V
575V
7.5
10
20
25
10
10
25
30
10
15
30
40
15
20
40
50
20
25
50
60
25
30
60
75
30
40
75
100
40
50
100
125
50
60
125
150
60
75
150
200
75
100
200
250
100
100
250
300
125
150
300
350
150
200
400
500
200
250
500
600
250
300
600
700
300
350
700
800
Soft Starter
UL
Amps
IEC
Amps
Catalog
Number
Size
28
34
42
54
68
80
104
130
156
192
248
302
361
480
590
720
840
30
37
44
50
72
85
105
142
175
210
250
300
370
470
570
720
840
1050
MST-030-CA
MST-037-CA
MST-044-CA
MST-050-CA
MST-072-CA
MST-085-CA
MST-105-CA
MST-142-CA
MST-175-CA
MST-210-CA
MST-250-CA
MST-300-CA
MST-370-CA
MST-470-CA
MST-570-CA
MST-720-CA
MST-840-CA
MST-1050-CA
A
A
A
A
A
B
B
B
C
C
C
C
D
D
E
E
E
E
Soft Starter Simulator Software
Save time during installation by simulating the MST Soft Starter
keypad interface on your PC. Practice setup. Simulate start, stop
and fault events. Available at no charge from the Baldor Website,
www.Baldor.com.
www.baldor.com
11
MST Digital Soft Starter - Enclosed
MST Digital
Soft Starter
Combination Starter with Circuit Breaker Disconnect
Enclosed NEMA Type 12/4 Combination Starter with Disconnect
MOTOR APPLICATION HORSEPOWER
Normal Starting
Class 10 - 400% torque for 30 seconds
208V
15
20
25
30
40
50
60
75
100
125
150
230V
20
25
30
40
50
60
75
100
100
150
200
460V
40
50
60
75
100
125
150
200
250
300
400
575V
50
60
75
100
125
150
200
250
300
350
500
Soft Starter
UL
Amps
IEC
Amps
Catalog
Number
Size
Weight
lb
54
68
80
104
130
156
192
248
302
361
480
50
72
85
105
142
175
210
250
300
370
470
MST-050-GD
MST-072-GD
MST-085-GD
MST-105-GD
MST-142-GD
MST-175-GD
MST-210-GD
MST-250-GD
MST-300-GD
MST-370-GD
MST-470-GD
A
A
B
B
B
C
C
C
C
D
D
70
72
105
110
118
210
226
230
240
343
352
Enclosed NEMA Type 12/4 Combination Starter with Circuit Breaker
MOTOR APPLICATION HORSEPOWER
Heavy Starting
Class 30 - 350% torque for 60 seconds
208V
15
25
30
40
50
60
75
100
150
230V
20
30
40
50
60
75
100
100
200
460V
40
60
75
100
125
150
200
250
400
575V
50
75
100
125
150
200
250
300
500
Soft Starter
UL
Amps
IEC
Amps
Catalog
Number
Size
Weight
lb
54
80
104
130
156
192
248
302
480
72
85
105
142
175
210
250
300
370
470
470
MST-072-GD
MST-085-GD
MST-105-GD
MST-142-GD
MST-175-GD
MST-210-GD
MST-250-GD
MST-300-GD
MST-370-GD
MST-470-GD
MST-470-GD
A
B
B
B
C
C
C
C
D
D
D
72
105
110
118
210
226
230
240
343
352
352
Severe Duty NEMA Type 4 Combination Starter with Circuit Breaker Disconnect
MOTOR APPLICATION HORSEPOWER
Heavy Starting
Class 30 - 350% torque for 60 seconds
208V
40
50
60
75
100
125
150
200
250
12
230V
50
60
75
100
100
150
200
250
300
460V
100
125
150
200
250
300
400
500
600
575V
125
150
200
250
300
350
500
600
700
www.baldor.com
Soft Starter
UL
Amps
IEC
Amps
Catalog
Number
Size
Weight
lb
130
156
192
248
302
361
480
590
720
175
210
250
300
370
470
570
720
840
MST-175-GS
MST-210-GS
MST-250-GS
MST-300-GS
MST-370-GS
MST-470-GS
MST-570-GS
MST-720-GS
MST-840-GS
C
C
C
C
D
D
E
E
E
223
228
237
244
373
399
649
681
687
MST Digital Soft Starter
MST Digital
Soft Starter
Combination Starter with Circuit Breaker Disconnect
Combination Starter Dimensions
Standard (inches)
H
Size
H
W
D
D1
MST-050 ...072 -GD
A
20.0
20.0
12.8
14.6
MST-085 ...142 -GD
B
24.0
24.0
12.8
14.6
MST-175...300 -GD
C
36.0
36.0
12.8
14.5
MST-370... 470 -GD
D
60.0
36.0
17.3
19.1
MST-570...840 -GD
E
72.1
37.1
25.2
27.0
Metric (mm)
SOLID STATE STARTER
W
D
D1
Size
H
W
D
D1
MST-050 ...072 -GD
A
508
508
325
370
MST-085 ...142 -GD
B
610
610
325
370
MST-175...300 -GD
C
914
914
325
369
MST-370... 470 -GD
D
1524
914
439
485
MST-570...840 -GD
E
1831
942
640
686
See previous page for combination starter weight
MST Digital Soft Starter
Accessories
External MOV
Catalog number
Volts
(Metal Oxide Varistor type voltage surge suppressor)
MOV505L
460
• Protect from line-to-line voltage spikes
MOV620EL
575
• Recommended for all low line impedance
applications
Remote Keypad with Cable
• 32 Character English alphanumeric display
Catalog number
MSTEK
Cable Length
10 ft.
• NEMA 4X indoor enclosure
• Backlit LCD
www.baldor.com
13
MST Digital Soft Starter
MST Digital
Soft Starter
Specifications
Rated insulation voltage Ui
690 V
Control circuit
Rated operational voltage Ue
208...600 V + 10 % / -15 % 50/60 Hz ±5%
Number of inputs
2 (start, stop)
100...250 V +10% / -15% 50/60 Hz ±5%
Number of additional
programmable inputs
2 (Each input can be programmed to
be either; Non, Reset, Enable, Jog,
DOL- On, Start motor 2, Start motor 3
or FB-Dis)
Rated control supply voltage
Us
Rated control circuit voltage
Internal or external 24 V DC
U
Starting capacity at Ie
4 x Ie for 10 sec.
Signaling indication LED
Overload capability
Class 10 and Class 30
Power on
Green
MST-030...840
MST-1050
Fault
Red
115 %
100 %
Protection
Yellow
Service factor
Protections
Ambient temperature
Electronic overload
Yes (Class 10A, 10, 20, 30)
Dual overload
Yes (separate overload function for
start and run)
PTC connection
Yes
Locked rotor protection
Yes (Level and delay adjustable)
Underload protection
Yes (Level and delay adjustable)
Phase imbalance
Yes (Level and delay adjustable)
High current (8 x Ie )
Yes
Full text
Phase reversal protection
Yes
English, German, Italian, Dutch, Chinese,
Finnish, Swedish, French, Spanish, Russian,
Portuguese, Turkish, Polish and Czech
Warnings (pre-warning)
during operation
±0 ... +50 °C
during storage
-25 ... +70 °C
1)
Maximum altitude
4000 m 2)
Degree of protection
MST-030...072
MST-085...MST-1050
main circuit
IP10
IP00
supply and control circuit
IP20
IP20
MST-030...300
MST-370...1050
No
Yes
Main circuit
Built-in Bypass contactor
Cooling system - Fan cooled Yes (thermostat controlled)
Keypad and display
Languages
Keys
Digital output
2 selection keys and 2 navigating keys
Form C contact
Number of programmable
signal relays
3 (each relay can be programmed to be
Run, Bypass or Event signal)
K4
Default as Run signal
K5
Default as TOR (Bypass) signal
K6
Default as Event signal
Rated operational voltage, Ue
250 V AC / 24 V DC
Rated thermal current Ith
5A
Rated operational current Ie
at AC-15 (Ue=250 V)
1.5 A
Type of output signal
Yes (Level and delay adjustable)
Low current (underload)
Yes (Level and delay adjustable)
Overload trip
Yes (Level and delay adjustable)
Overtemp, thyristor (SCR)
Yes
Start of several motors
Possible to set up and start three
different motors
Switch off resistance
2825 ohm ± 20%
Switch on resistance
1200 ohm ± 20%
External keypad
Display
LCD type
Ambient temperature
0 ... 10 V, 0 ... 20 mA, 4 ... 20 mA
During operation
±0 ... +50 °C
I Amp, U Volt, P kW, P hp, Q kVAr, S kVA,
TmpMot, TmpSCR, cosPhi
During storage
-25 ... +70 °C
Degree of protection
IP66 (Indoor)
1)Above 40°C up to max. 50°C reduce the rated current with 0.8% per deg. C
2)When used at high altitudes above 1000 meters up to 4000 meters, derate the rated
current using the following formula:
[% of Ie = 100 - (x-1000)/150] where x = actual altitude of the soft starter
14
Yes (Different parameter sets)
PTC Thermistor input
Analog output
Output signal reference
High current
www.baldor.com
MST Digital Soft Starter
MST Digital
Soft Starter
Trip Curves for the Integrated Overload Protection
All units have an integrated electronic overload protection. It is
possible to set it on four different tripping classes.
The chart below shows a curve for each tripping class from a
cold state.
Time (s)
10 000
1000
100
Class 30
Class 20
Class 10
Class 10A
10
1
0
0
1
2
3
4
5
6
Tripping curves for electronic overload protection for MST Soft Starters from a cold state.
www.baldor.com
7
8
Current (x Ie)
15
Contact your nearest Baldor Sales Office at these
World Wide locations, or visit www.baldor.com
© Baldor Electric Company
BR852
Baldor Electric Company
P.O. Box 2400
Fort Smith, AR 72902-2400 U.S.A.
Ph (479) 646-4711 • Fax (479) 648-5792
International Fax (479) 648-5895
www.baldor.com
Printed in U.S.A.
01/14 TCP 5000