Service manual

Electrical Service Manual V4.0

11-1

ELECTRICAL COMPONENTS

COMPONENTS

SWITCHES

We use a number of different switches on our machines. Many of them look very similar on

the outside but it is the conﬁguration of the contacts inside that makes them function differ-

ently.

Switches are deﬁned in 3 ways; poles, throws and action.

A POLE refers to the number of cirrcuits in a switch.

A THROW refers to the number of ways a pole can connect.

The ACTION is how a switch responds to being moved. It can

either creata a momentary contact or a maintained contact.

Poles:

SINGLE pole allows 1 circuit to be switched (SPST)

Double poles allow 2 circuits to be switched (DPST)

Throws

Single Throw (SPST)

Double Throw (SPDT)

TYPICAL SWITCH CONTACT CONFIGURATIONS





 

DPDT

DOUBLE POLE

DOUBLE THROW

SPDT

SINGLE POLE

DOUBLE THROW

DPST

DOUBLE POLE

SINGLE THROW

SPST

SINGLE POLE

SINGLE THROW