4.2.1 Control unit for LIFT with mechanical safety devices
Platform lifting is carried out by the hydraulic unit which acts upon the primary cylinder.
The platforms are raised simultaneously owing to cross feeding of the hydraulic cylinders.
Lowering, even though electrically controlled, is carried out by the weight of both the platforms and
the load lifted.
The hydraulic system is protected by a pressure relief valve thus preventing pressure from exceeding
the maximum safety limit.
Lifting and lowering motion of the lift is controlled by the push-buttons on the control panel.
Whenever the lift has to be lowered to the ground and the DOWN button is pressed, the lift will stop
at about 400 mm from the ground.
In this way, the operator can verify that neither persons nor objects are within
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4.3 Operation
The control unit is composed of:
1
A supporting frame.
2
Cover panels.
3
A head unit.
4
Control panel.
5
Up button.
6
Down button.
7
End of travel button
(last 400 mm)/safety devices.
8
Identification labels
and safety
labels.
9
Warning light.
10
Main switch.
11
Main hydraulic
unit.
12
Oil tank.
13
Electric motor.
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