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
www.baldor.com
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
www.baldor.com
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
www.baldor.com
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.
www.baldor.com
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
www.baldor.com
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
www.baldor.com
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