Manitowoc MLC650, Service Maintenance Manual

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Reference
Only
ACCESSORIES MLC650 SERVICE/MAINTENANCE MANUAL
10-70
Published 09-09-16, Control # 229-09
High Load Operation—Compression
See Figure 10-57 for the following.
When the active fixed mast stop (AFMS) system needs a
higher load capability from the mast stop cylinder, the mast
cylinder directional control solenoid valve (7) and the mast
cylinder pressure-reducing solenoid valve (5) are de-
energized. The higher cylinder pressure causes the check
valve (6) to close, isolating the cylinder side of the circuit.
As the cylinder is compressed from the load and when the
pressure reaches 221 bar (3200 psi), the relief valve (2)
opens, allowing the hydraulic fluid to flow from the cylinder
bore to the integrated cylinder accumulator (3), charging the
accumulator.
A small portion of the hydraulic fluid stored in the
accumulator flows through the relief valve (4) and back to the
tank.
High Load Compression
Item Description
1 Mast Stop Cylinder
2 Relief Valve (set at 221 bar [3200 psi])
3 Integrated Cylinder Accumulator
4 Relief Valve (set at 16,6 bar [240 psi])
5 Mast Cylinder Pressure-Reducing Solenoid Valve
6 Check Valve
7 Mast Cylinder Directional Control Solenoid Valve
8 Rupture Disc
9 Bypass Check Valve
10 Mast Cylinder Pressure Transducer
11 Mast Cylinder System Pressure-Reducing Valve
(set at 31 bar [450 psi])
12 Mast Cylinder System Pressure Transducer
FIGURE 10-57