Contactor symbol
Also called Motor contactor, Starter
A contactor is an electrically operated switch for frequent switching of loads, usually motors. It does not clear faults on its own; it is paired with fuses or a breaker and an overload relay.
What the contactor symbol means
A contactor is an electrically operated switch for frequent switching of loads, usually motors. It does not clear faults on its own; it is paired with fuses or a breaker and an overload relay.
ANSI and IEC symbols
A normally open contact, two parallel lines, marked M or with the starter size.
ANSI SVGWhere you see it
Motor starters in motor control centres, capacitor bank switching.
What is written next to it
On a one-line, the contactor carries its tag and its ratings: utilisation category (for example AC-3), rated current and coil voltage.
What gets checked at commissioning
Before the contactor is energised, the test records usually cover: coil and operation, the overload relay setting, interlocks and the control circuit. Each check is recorded against the tag, so the system can be handed over with its evidence. See commissioning software.
ANSI device numbers
Protective functions you will often find with a contactor:
- 42 running breaker or contactor
- 49 thermal overload
See the full list of ANSI device numbers with their IEC equivalents.
Related symbols
Frequently asked questions
What does the contactor symbol look like?
On ANSI drawings: A normally open contact, two parallel lines, marked M or with the starter size. In IEC 60617: A switch with a half circle at the fixed contact. The half circle is the contactor function, S00218.
Is the contactor symbol the same in IEC and ANSI?
No. A switch with a half circle at the fixed contact. The half circle is the contactor function, S00218. The IEC 60617 number is S00284.
Where is a contactor used?
Motor starters in motor control centres, capacitor bank switching.
Which ANSI device numbers go with a contactor?
42 running breaker or contactor, 49 thermal overload.
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