USER MANUAL
– Safecheck
5
32"
80 cm
M1
3.
Principles
3.1 How the hydraulic system works
The Safecheck is an hydraulic weighing system for forklift trucks and stackers. The load measurement
system measures the oil pressure with an oil pressure sensor.
The pressure in the lifting system
depends on the load on the fork lift system. By measuring the oil pressure in the cylinder,
you will get an indication of the weight that you are lifting.
3.2 The reference height
To reduce the influence of the condition of the mast and the cylinder, the weighing is always
performed at the same height. To ensure this, stickers are placed on the mast and carriage plate to
clearly mark the reference height at which the weighing should occur.
First lift the forks past the reference point and then lower the load to the point where the stickers are
opposite each other. This results in the optimal accuracy.
3.3 Accuracy
Meassuring the oil pressure is a very precise job, but mechanical parts in the lifting mechanism
and the position of the mast can adversely affect the accuracy.
The friction/resistance of the roles with which it moves in the mast is a major influence on the
weighing. The resistance of the coils by dirt or bad bearings increase the inaccuracy caused by:
•
internal leakage in the oil circuit;
•
eccentric load of the forks (the load is not centered on the forks);
•
the difference at slow or fast approaching of the reference altitude.
With more ' stick and slip effect ', there is less repeatability, so less accuracy. Repeatability means that
when you meassure the same weight in succesion, every time about the same weight appears in the
display.
