Series; Parallel; Series/Parallel; Types Of Failures - MTD 188 Professional Shop Manual

ELECTRICAL SYSTEM

Series

• Series circuits are wired so that the current has
only one path to follow. See Figure 2.5.
Switch
Battery
Figure 2.5

Parallel

Parallel circuits are wired so that current has multiple
paths to follow. See Figure 2.6.
Figure 2.6

Series/parallel

Series/parallel circuits have some sections wired in
series and some in parallel. See Figure 2.7.
Bulb

Types of failures

There are three types of failures that can occur in an
electrical circuit:
1.
2.
3.

Shorts

A short is when electricity takes a path that it was not
designed to take bypassing a component in the circuit.
An common example of a short is the wire that chafed
through. The bare copper will short the circuit when it
touches a ground source.

Opens

An open is when current can not complete its path back
to the power source.
A common example of this is a blown fuse.

Increased resistance

Increased resistance is as the name implies, an
increase in resistance.
Arguably the most common electrical failure, and the
hardest to find, it is when there is a loose connection or
corrosion. It is not an open because there is some cur-
rent that can get through, but the increase in resistance
is enough to affect the circuit
6
Figure 2.7
Shorts
Opens
Increased resistance