JLG 450AJ Service Manual - Manual (Page 68)

SECTION 2 - PROCEDURES
2-52 – JLG Lift – 3120869
R.T.O. (Ramp Thru Off)
This controller is configured with an enhanced ramp fea-
ture that allows the handle to released or moved from one
handle extreme to the other without canceling the ramp
duration. The RTO duration is factory set to 2 seconds
Adjustment Procedures
NOTE: The following procedures are for a preliminary
adjustment. Final Adjustments are to be based on
the function speed of the operation.
NOTE: The trimpot adjustment screws are multi turn
devices. No harm can come to the trimpot if it is
turned too much. The trimpot will "click" when the
wiper is at the end of the element. It may be neces-
sary to turn the adjustment screw several turns to
observe a change in the output.
The most reliable measure of the performance of the func-
tion you are fine tuning is to monitor your adjustments
until the desired speed is achieved. Have the machine
fully operational in an area where obstacles are not
present. Use your meter to monitor the current output,
and record that number once you have set the function to
the proper speed.
The EMS4M11100 is equipped with a ramping option.
Adjustment and calibration may be difficult due to outputs
ramping up to their set level. When making adjustments,
let the output stabilize before recording that setting.
The Drive/Steer controller is set by Milliamps. To adjust the
Drive/Steer controller, turn the trimpots clockwise to
increase and counterclockwise to decrease milliamps. All
of the trimpots are 25 turn type.
1. At the platform control box install an amp meter
inline between the orange wires at terminal #10 for
forward and terminal #11 for reverse.
2. The threshold trimpot is set at 15 to 25 ma. The Low
Range trimpot is set at 60 ma. The High range trim-
pot is set at 130 ma. To set the Threshold trimpot,
stroke the joystick until the red LED glows. With the
function speed control off of the snail position,
adjust the trimpot to 15 to 25 ma. This should be just
enough amperage to start the drive wheels moving.
3. Adjust the High Range trimpot. Stroke the joystick
fully with the function speed control off of the snail
position. Turn the trimpot until 130 ma is displayed
on the meter.
4. Adjust the Low Range trimpot. With the joystick fully
stroked and the function speed control at the snail
position, adjust the Low Range trimpot until the
meter reads 60 ma.
NOTE: Milliamp readings should be the same for Drive for-
ward and reverse.
5. Adjust Ramp to provide a smooth start and stop
function.
Figure 2-35. Drive and Steer Adjustment