Toyota 7BPUE15, Руководство по обслуживанию

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Toyota Orderpicker Model 15 Service Manual Section 5. Troubleshooting
Definitions
Continuity
A continuous and uninterrupted path between
two or more locations in a n electrical circuit,
typically having a resistance of less than 1 ohm.
Switches
The switches in the truck that must be closed to
allow truck operation. The Orderpicker Model
has two switches under the
pedal. Both switches must be
functional for the truck to travel, lift or steer.
Stepping on the pedal on the operator platform
activates these switches. The function
acts to protect against travel while the brake is
applied.
M 3 and M 4 Accel Rate
The time necessary to reach full output
from zero output in M3 or M4 (high speed,
PMC-3 on) mode. See Table 5-7 on page 5-24.
M3
and M 4 M a x Speed
Maximum speed (PWM duty factor) in M3 or M 4
(high speed) mode.
Mode Select Inputs
The traction power amplifier is capable of four
modes of operation that are determined by two
mode select inputs
and from the
manager. See Table 5-4 on
page 5-22.
Neutral Braking
The plugging force applied to the drive motor by
the power amplifier when the throttle is in
neutral
with the switches closed.
Open Circuit
Definitions
Overtemperature (Traction Power
Amplifier)
Overtemperature of the traction power amplifier
is
C and above. Overheating is
unusual, but can occur if the traction power
amplifier is installed incorrectly or overloaded.
At overtemperature the drive current limit is
linearly decreased from full set current down to
zero. Plug current is not reduced by any
thermal conditions to allow full plugging
strength a t all times.
Pulse Width Modulation
Pulse Width Modulation also called
"chopping," controls the speed of the motor by
switching the battery voltage to the motor on
and off very quickly.
Short Circuit or "Short"
A short circuit is a n unspecified path in a
circuit that provides unwanted full or partial
continuity between two or more locations in a n
electrical circuit.
Example: Two insulated wires are physically
next to each other and the insulation has been
worn off each of the wires. Because the
conductors inside each wire are now touching
each other, there is a short circuit.
Example: A power cable from the battery to a
junction post in the truck has had the
insulation worn away. Because the wire
conductors are touching the tractor frame,
there is a short circuit of the battery cable.
Undertemperature
When the amplifier is operating a t less than
C the current limit is cut back
resulting in reduced travel speed and
acceleration.
A lack of a continuous path between two or
more electrical connections.
00700-CL222-05, 1 5 March 2005