Hanna Instruments HI 8050 - Manual (Page 51)

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This panel allows the setting of the flow parameters. The sector number in-
dexes this panel. This panel displays and allows the setting of the following
parameters:
− Flow -
Flow - Flow - Flow - Flow - The selectable volume percent for the indexed sector. It is used to
calculate the water used on each sector based on the total amount of
water measured by the main counter.
− Sect Sect Sect Sect Sect - The panel index. The sector number (label).
− Max. time Max. time Max. time Max. time Max. time – the time-out after which the main counter fail alarm is trig-
gered.
− L / impulse L / impulse L / impulse L / impulse L / impulse – The counter factor for the main counter.
How to set the flow parameter:
The total quantity of water is known if we use a counter on the main
pipe, this quantity of water must be divided among the opened sectors. We
must bear in mind that the pipes might not be the same therefore the controller
needs information about the section of pipes. This information is offered by the
Flow parameter. These values must be set correctly for the statistics and the
volume control to work correctly.
1. First step is to find the diameter for the pipes that guide the water to
the sectors.
2. Second step is to find the sector that has the pipe with the maximum diam-
eter. For that sector we set the flow parameter to 100.
3. The next step is to compute the flow for the sectors using the
formula:
where:
- dmax is the maximum diameter used for the sector pipe
- dsect is the diameter of the sector pipe for the current sector
- Flow sect is the sector for which we set the flow
EXAMPLE:
1. For instance let us consider that the installation has these
diameters for the pipes that bring water to the sectors: 1 inch, 1.5 inch
and 2 inch. This is equivalent to the first step where the pipes are
measured.
2. The pipe with the maximum diameter is the 2 inch pipe, for
that pipe we set the flow parameter to 100.
3. Compute the next Flows:
3.1. for the sectors with 1 inch pipe:
3.2. for the sectors with 1.5 inch pipe:
3.3 for all the sectors with a 2 inch pipe the flow is set to 100
NOTE: we consider the diameter of the sector pipe the internal