Specifications
35
Motor Starters Although safety switches can be used to start and stop
motors, many motor applications require the use of remote
control devices to start and stop the motor. Motor starters are
commonly used to provide this function. In addition, some
motor starters have multi-speed and reversing capability. When
the motor starter is contained in the same enclosure with a
fusible disconnect switch or circuit breaker, it is referred to as a
combination starter.
Safety Switch
Motor Starter
Motor
Contactor
Overload
Relay
A motor starter typically consists of a contactor and an
overload relay. A contactor is an electromagnetic device with
contacts that control power to a motor. An overload relay
prevents damage to a motor by automatically stopping the
motor when an overload occurs.
Pushbuttons and other types of control components are used
in the control circuit for a motor starter to energize and de-
energize the contactor and perform other functions.
Siemens manufactures a variety of motor starters and other
control components. Some of these components, such as those
that are part of our SIRIUS Modular System, are manufactured
to International Electrotechnical Commission (IEC)
speciļ¬cations. Siemens also manufactures a full range of control
products that conform to NEMA speciļ¬cations.
Contactor
Overload Relay
C
O
IL
N
O
.
11
0
V
L
1
L
2
L
3
T
1
T
2
T
3
3
2
Vol
tes 3 P
h
Max
HP
M
ax
Amp
s
Ser
ies
A
600 V
AC
SE
&A
Inc.
Alpharet
ta, G
A U
.S.A
.
ESP200
TEST
RESE
T
FULL
LO
A
D
AM
PS
T
R
IP
C
L
A
S
S
5
1
0
2
0
3
0
P
H
A
S
E
U
N
B
A
L
O
N
P
H
A
S
E
L
O
S
S
O
N
R
E
S
E
T
M
O
D
E
M
A
N
.
G
R
O
U
N
D
F
A
U
L
T
O
N
Contactor
Overload Relay
SIRIUS 3R
IEC Starter
NEMA Starter