Sterlco SGBD Series Batch Gravimetric Blenders - Manual (Page 19)

BLN1-600A Chapter 2: Functional Description 19 of 116
Figure 6: Typical Slide Gate Assembly
Each of the diamond gate air cylinders is actuated by a solenoid valve, which are controlled
by the blender PLC.
When the solenoid valve is energized, it opens the metering valve cylinder. When the
solenoid valve is de-energized, it closes the metering valve cylinder.
If the power is interrupted to the blender, the metering valves will return to the closed
position, to prevent material from over-filling the weigh hopper/mix chamber.
Weigh Hopper
On a Slide Gate blender, the weigh hopper rests on each side on a precision cantilever load
cell. To remove the weigh hopper, disconnect air line then lift the hopper from the bottom,
hold the dump door closed, and slide it out once clear of the locating tab on the bracket above
the load cell.
Once the hopper has been cleaned, reposition it onto the load cell brackets, using care not to
damage the load cells. Position the hopper as close to the center position between the load
cells as possible.
• If the blender is in metering mode with one of the slide gates open, do not
open the front door of the blender!
• The safety switch shuts off the air supply to the blender. An open feeder
slide gate stays open, and an overflow of the weigh hopper can occur!
• Use care when replacing the weigh hopper, since the load cells are delicate
weighing instruments and can be easily damaged. Do not use force to push in
the weigh hopper. If it is positioned properly, it will slide in very easily.
• Load cells, if damaged, will have to be sent back to the manufacturer for
testing and evaluation.