Sterlco SGBD Series Batch Gravimetric Blenders - Manual (Page 55)

Bulletin Number Chapter 4: Operation 55 of 101
Selecting “Mixing Time” from the “Mixer and Dump Setup” menu will allow the operator to
view the current time setting for the mix timer and to adjust it as needed.
The mix timer is set to a default time of four (4) seconds. This time can be adjusted up or
down depending on the amount of mixing needed for the materials being blended.
It is recommended that the mix time be held to the minimum, as segregation can occur from
over-mixing if the material bulk density and pellet configuration varies with materials in the
particular blend being processed.
Re-Mix Timer
In some applications, the Slide Gate/Auger blender will require the use of the re-mix timer.
Some materials tend to separate if they are mixed too long. This is possible when a
processing machine is running at a rate significantly below the capacity of the blender.
With external vibration, the heavier pellets will tend to flow to the bottom of the mix chamber
before the lighter material. This will occur even though the mixer is in a static mode. By re-
mixing occasionally, this situation will be prevented.
The re-mix timer will start another mixing cycle if the blender has been idling long enough
for the re-mix timer to time out. The re-mix timer may be set on the “Mixer and Dump Setup”
screen from 1 to 999 seconds. Setting the re-mix timer to zero will disable this function.
If the re-mix timer is disabled, the controller will run only a single, timed mix cycle after each
dump of the weigh hopper.
To view and change the value of the re-mix timer, refer to the “Mixer and Dump Setup”
menu. All current values for Mixing and Remixing Times will be shown on this screen. The
re-mix timer default value is factory preset at zero.
Weigh Hopper Dump Time
The weigh hopper dump time is the amount of time the weigh hopper’s dump valve remains
open to allow weighed material to exit the hopper and enter the mixer.
To view and change the current weigh hopper dump time settings, enter the Setup menu and
select the “Mixer and Dump Setup” screen. Press the field next to “Dump Time” to set the
operation of the Dump Valve.
The dump timer on the dump valve has a default time of four (4) seconds. This time can be
adjusted to optimize the blender cycle time.
The timer should be set to close the dump valve shortly after the material has totally dumped
from the weigh hopper. This time can vary due to material flow characteristics, and the size
of the batch that is programmed into the blender control. Experimentation with this setting
can allow the operator to determine the best cycle for the material being weighed.
Weigh Hopper Dump Delay Time
The dump delay time is the amount of time from the end of metering the last ingredient until
the start of the actual dump cycle. The start of the dump cycle is marked by the opening of
the weigh hopper dump valve. This value has a range from 1 second to 999 seconds. To view
and change the current dump delay time, enter the Setup Menu, select “Mixer and Dump
Setup” screen, and then select “Dump Delay”.
The default time is factory set at zero seconds. This delay time is used to start the mixer prior
to dumping the material from the weigh hopper into the mix chamber of the blender.