Dynapac SD2500W, Operation & Maintenance Manual

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D 43 27
Screed charging/relieving
This function charges or relieves the screed regardless of its own dead weight.
Function (70)
Relieving (screed "lighter")
Function (71)
Charging (screed "heavier")
A
The "Screed charging and relieving" functions are only effective when the paver fin-
isher moves. According to the activated function, the paver finisher is automatically
switched to "paving stop + relief" when stationary.
Screed control with paver finisher stop / in paving operation
(screed stop / paving stop / floating paving)
Button (63) can be used to activate the following functions:
- Screed stop / floating position (OFF)-->(LED OFF)
- Screed is hydraulically held in position.
A
Function for setting up the paver finisher and for lifting/lowering the screed
- Paving stop / floating paving (ON)-->(LED ON)
The following functions are active depending on operating status:
- "Paving stop": when the paver finisher is stationary.
The screed is held by the relief pressure and the counter pressure of the material.
- "Floating paving": during paving operation.
Lower screed to the floating position with preselected screed charging/relieving
function.
A
Function for paving operation.
- To lift the screed press switch (68).
- To lower the screed:
- Resting function: Keep button (63) pressed for longer than 1.5 seconds. The
screed is lowered as long as the button is pressed. When the button is released,
the screed is stopped again.
- Button function: Press button (63) briefly - the screed is lowered. Press the button
briefly again - the screed is stopped.
As in the case of screed charging and relieving, a pressure of 2-50 bar is separately
applied to the screed lifting cylinders. This pressure acts to combat the weight of the
screed to prevent the screed from sinking into the freshly laid material, thus support-
ing the paving stop function, especially when the screed relieving function is used.