Wiring Diagram/Description - Stihl E 140 Service Manual

3.

WIRING DIAGRAM/DESCRIPTION

1
2
1
1 Trigger switch
2 Capacitor (230 V only)
3 Overload circuit breaker (E 160, E 180 C only)
4 Chain brake switch
5 Brush holder with carbon brush
6 Rotor
7 Stator
The trigger switch (1) is equipped
with a mechanical starting lockout
(interlock button) which helps pre-
vent unintentional switch-on.
The saws feature a thermal over-
load circuit breaker (3) to protect
the electric motor from mechanical
overload.
This overload circuit breaker inter-
rupts the power supply to the saw
if the operator continues cutting for
an extended period with an over-
tensioned chain, uses excessive
feed force, "lugs down" the motor
speed or if the chain is suddenly
stopped by being pinched in the
cut.
2
2
1
7
Before restarting the saw and con-
tinuing work it is necessary to pull
the guide bar out of the cut and
wait for a short period until the
overload circuit breaker has coo-
led down. The overload circuit
breaker can then be reset by pres-
sing in the button as far as
the stop.
This is not a fault. The remedy in
such a case is to work with less
feed effort. Under no circumstan-
ces should the overload circuit
breaker be bypassed, even if the
owner explicitly requests such a
modification.
Chain brake
3
The brake lever is unlatched when
the "Quickstop" chain brake is
1
activated, either manually or by
K
3 inertia. The power supply is inter-
2
rupted immediately by the chain
brake switch (4) and the spring-loa-
ded brake band is clamped around
the brake drum at the same in-
2
4
stant.
This causes the saw chain to be
brought to a standstill and locked
in position. The chain brake is
disengaged by moving the hand
guard toward the front handle.
5
Coasting brake
The coasting brake supplements
the chain braking system. It brings
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the rotating chain to a standstill
when the operator releases the
trigger switch.
In the idle condition, an additional
spring clamps the brake band aro-
5
und the brake drum.
When the trigger switch is squee-
zed, the brake band is first disen-
gaged from the brake drum via a
linkage. Only then does the switch
close and start the motor.
5