
8CB-1 Installation/Operation Manual
Splt Evn
This selection is similar to optimize in that it
allows a batch up to four times the size of the
plant, but it splits up the drafts differently. Splt Evn
tries to “split even” the draft size. For example, a
19 yard batch would require three 6.33 yard
batches. The advantages of this is that all batches
are the same size and usually not real small. This
is good since consistency usually means accuracy.
The disadvantage is that the individual drafts may
be an odd number such as 6.33 yards or 3.67
yards.
Even 1/4
This is the same as Splt Evn except it rounds the
draft yards to the nearest 1/4 yard to prevent odd
draft sizes mentioned above. Using the same
example as above, a 19 yard batch on an 8 yard
plant would be broken up into two 6.25 drafts, and
one 6.50 yard draft.
5.1.5 Batch Type
You can choose between three types of batching:
•NET
•GROSS
• SEEKIDL
See the following parameter definitions.
Net
This option causes the indicator to always read the
net weight for the ingredient being weighed. This
is accomplished by the CB-1 sending a tare
command to the appropriate indicator before each
ingredient is weighed. In addition, the target and
actual weights displayed on the screen during
batching and printed on the batch ticket are net
values and do not include any starting weight or
the weights of any other ingredient weighed in
that hopper. The % difference is calculated per
ingredient. After all ingredients are weighed up,
the CB-1 sends a command to the indicator
changing them back into gross mode for
discharging.
Gross
In this mode, the indicators always remain in the
gross mode and are never tared. For the first
ingredient delivered in each weigh hopper, the
CB-1 includes any weight on the scale as part of
the target weight. After the first ingredient has
been delivered, the CB-1 calculates the
cumulative target weight for the next ingredient
based off the settle weight of the previous
ingredient. In both gross and net modes, the net
target weight for an individual ingredient is
independent of the weight on the scale; however,
the gross target weight (weight reading on the
indicator) for the 2nd, 3rd and 4th ingredients will
include any previous weight on the scale plus the
net target weight for the current ingredient.
For example:
AGG1 target=1000 and AGG2 target =1000.
If the aggregate scale starts at 10lb the target for
AGG1 will be 1000 for either net or gross modes.
Let’s say that AGG1 was overfilled to 1020. In net
mode, the scale will be tared and will display 0
(net), so the target weight for AGG2 would be
1000 (0 + 1000 = 1000).
In Gross mode, the target weight for AGG2 would
be 2020 (1020 + 1000 = 2020). Of coarse the
individual target weight for AGG2 was 1000 in
both cases.
As in net mode, gross mode batching displays and
prints the individual (net) weights for target and
actual net weight delivered on the screen and
reports. To avoid confusion between cumulative
and net weights on a batch ticket, “target” is
replaced with “req’d” (required) for individual net
weights and “actual” weight batched per
ingredient.
Seek Idl
Seek Idl targets is like gross mode in the fact that all
indicators are never tared and remain in gross
mode during batching. One difference is that the
cumulative “ideal” targets are calculated for all
ingredients and do not compensate for over and
under amount of previous ingredients. The
purpose of this is to make sure the total aggregate
and cement amounts are accurate. This, however,
has a tendency to change the proportions of sand
to rock, or cement to fly ash. In the previous
example, the target for AGG1 would be 1000 and
the target for AGG2 would be 2000, regardless of
the fact that AGG1 actual delivered was 1010.
Another difference is that the tolerance is then
calculated based on the total aggregate weight. If
we were allowed 2.0 % tolerance on aggregates
then in “Seek Idl” mode we would be allowed 20
lbs. on AGG1 and 40 lbs. on AGG2 since the
target was 2000 (2000 X 0.02 = 40). Another
difference is that all values for target and actual
that are displayed or printed are the true
cumulative values that should appear on the
indicator.
5.1.6 Force Zero Tolerance Check
Setting this value to Yes does not allow a batch to
begin until the scale is within zero tolerance as
defined in Section 5.3 under “Zero Tolerance.”