As standard all Pentalift hydraulic lift tables are provided with a hand held Up/Down constant pressure push button on a 10’ cord. https://www.pentalift.com/solutions_category/pre-engineered-lift-postioning/
To raise the lift table platform depress and hold the Up button, to lower the lift table press and hold the Down button. Releasing either button will stop the platform movement at the desired position.
A guarded 2 button constant pressure foot pedal control station is an option available to control the lift table positioning; this option keeps the operators hands free to perform tasks such as assembly work, product positioning etc.
In some applications the operator is on the lift table platform as the lift table raises and lowers. In these applications in addition to guard rails on the platform, checker plate deck for improved traction, access chains, interlocked gates etc. it is common to have the Up/Down control station installed on a post on the platform.
The push button control station can be ordered permanently attached to the post on the lift table platform or removable from the post. A removable push button station assures that only authorized personnel are permitted to connect the controller and operate the equipment.
Lift tables are available with 2 control stations. There are many combinations of dual controls; it is not uncommon to have a wall mounted control station at the upper level and a wall mounted control station at the lower level. This configuration permits the operator to “call” or operate the lift table from either elevation. Lift tables equipped with dual controls automatically include an EStop emergency button located in each control station.
The majority of lift table power units are remote or external to the actual lift table. Lift tables that are used as an elevated work platform often have the controls installed on the platform and can be ordered with a manual lowering valve installed on the power unit. In the unlikely event of a power failure or an emergency on the elevated platform the lift table can be safely lowered by manually opening the power unit located lowering valve. https://www.pentalift.com/solutions_category/custom-highlifts/
In an application that requires the lift table platform to stop at an upper elevation repetitively such as between two floor levels or the platform raises to a fixed conveyor height etc. the lift table can be equipped with an Up Travel limit switch. The Up Travel limit switch is Factory pre-set to the specified height and can be adjusted for precise positioning at time of equipment installation.
Lift tables that are installed in a preformed recessed pit must have the lift table platform equipped with either 4 sided beveled toe guards or electric toe sensors. Either of these options is required to remove a potential shear hazard as the platform lowers into the recessed pit.
Electric toe sensors consist of a 4 sided steel bar that is suspended under the bottom edge of the lift table platform. This option features 4 limit switches that are wired in a series circuit between the down button and the electric lowering valve; in normal lowering operation the 4 limit switches are closed.
When lowering if the suspended toe sensor bar contacts the operator’s foot or debris at least one of the limit switches open circuits. An open circuit breaks the signal flow from the Down button to the electric lowering valve, the lowering valve closes and the platform stops lowering. When the operator pulls back their foot or the debris is removed the operator depresses the Down button to lower the platform.
The majority of hydraulic lift tables have a selection of power units to choose from. The power unit selection is based on the applications lifting speed requirements. The power unit consists of 5 primary components, the lift motor, the gear pump, the oil reservoir, an electric lowering valve and a control system.
To increase the lift speed the power unit can be supplied with a higher volume output gear pump. The higher volume output gear pump increases the oil flow volume to the lift cylinder(s) causing the lift cylinder(s) to extend quicker raising the platform quicker. To drive the higher volume pump a higher HP rated lift motor is required.
A hydraulic velocity fuse monitors the oil flow rate from the lift cylinder(s) back to the reservoir as the lift table platform lowers. In the unlikely event of a severed hydraulic hose the oil flow rate from the cylinder(s) increases significantly. Velocity fuses are rated in gallons per minute of oil flow, if the oil flow rate surpasses the velocity fuse GPM rating the velocity fuse immediately closes trapping the hydraulic oil in the cylinder(s) preventing the platform from lowering. The velocity fuse may not lock with a light load or no load on the platform if the lowering speed is within the manufacturer’s acceptable rate of descent.
For additional information on any Pentalift product please contact the Pentalift Sales Department.