JLG EMERGENCY DESCENT – ARTICULATED – 1250AJP

From Ground

Platform or Boom Caught Overhead or Boom Movement
Prevented by Boom Control System
Lowering the boom onto an object or structure may cause the boom control system
to prevent movement of the machine. This can include movement necessary to lift
the boom off the object. Additionally, if the platform or boom becomes jammed or
snagged in overhead structures, movement of the boom can be regained by doing
the following:

1. Shut off the machine.
2. Rescue all people in the platform before freeing the machine. Personnel must
   be out of the platform before operating any controls on the machine.
3. Use cranes, forklifts, or other equipment to stabilize motion of the machine to
   prevent a tip over as required.
4. From the ground controls, use the Auxiliary Power System to carefully free the
   platform or boom from the object.
5. Once clear, restart the machine and return the platform to a safe position.
6. Inspect the machine for damage. If the machine is damaged or does not
   operate properly, turn off the machine immediately. Report the problem to the
   proper maintenance person

Using the auxiliary power system

The auxiliary system is used when there is an engine malfunction and you need to move the platform back to ground level. It uses an electric motor/pump to operate the boom hydraulics.

1. Engine must not be running.
   The auxiliary system is disabled when the engine is running.
2. At the ground control station, pull out the Power/Emergency Stop.
3. Select the appropriate control station using the Platform/Ground Select switch.
4. At the ground controls, hold the Engine Start/Auxiliary Power switch DOWN.
   It must remain held down for the entire period that auxiliary pump operation is required.
5. While holding the auxiliary power switch down, operate one boom function at a time.
6. To lower the platform, the system is designed to use gravity where possible for:
   • Main Lift DOWN
   • Tower Lift DOWN
   • Tower Telescope IN
   If the boom sensors don’t detect sufficient movement, the auxiliary pump automatically supplies hydraulic flow to assist the movement.

Important for the 1250AJP

Do not operate more than one function at a time. JLG specifically warns that simultaneous operation can overload the auxiliary pump.