Teledyne 4250, Инструкция по установке и эксплуатации, Страница: 70 / 204

4250 Flow Meter
Section 2 Programming
2-42
Enter Maximum Head
Before advancing from step 2 (Flow Conversion) to step 3
(Adjust Parameters), the flow meter will request that you enter a
value for
Maximum Head (Level) for the device or flow con-
version you are using.
For most standard measuring devices this information is pub-
lished or is available from the device manufacturer. Note that
you should
not arbitrarily use the largest value available.
Instead, use the value that is the largest expected level for
your actual situation, even if this is less than the published
maximum.
The flow meter’s internal resolution and its accuracy are based
on the value you enter for Maximum Head. The flow meter will
display:
Programming the 4-20 mA Outputs
Note
If you do not turn on the 4-20 mA output(s) in step 1, the
menus determining its (their) operation will not even appear
later in the program. If you need this function and cannot find
the appropriate menus in
step 2 , return to step 1, Setup and
check to see that you have not inadvertently switched the
option off.
If you turn on any of the 4-20 mA outputs (ANALOG OUTPUTS)
in
step 1- Setup , programming the actual operation of the
output appears in step 2 - Select Flow Conversion . For each
4-20 mA output port turned on, the flow meter will request entry
of the type of data that will drive the output, along with
minimum and maximum values. Here is an example of what you
might see for programming analog output 1.
TEMPERATURE, DISSOLVED OXYGEN, CONDUCTIVITY,
SPECIFIC CONDUCTANCE, SALINITY, and TOTAL DIS-
SOLVED SOLIDS may also appear as driving conditions.
The actual choices available to you will depend on what ports you
have turned on previously and what accessories (YSI, pH, DO
probes, rain gauge, etc.) you are using with your flow meter. After
you select one of the choices available to you, the flow meter will
request that you enter minimum and maximum values for that
choice:
Note that 4 MA in the second line of the display could also be 0
MA if that is what you selected for the current loop minimum in
Setup . The units are the units of measure appropriate for the
option you selected; for example, feet or meters for level, degrees F
FLOW RATE AT MAXIMUM HEAD
X.XXX CFS ( or other units of measure )
DATA TYPE FOR ANALOG OUTPUT 1
• (OFF)••(LEVEL)••(FLOW RATE)••(VELOCITY)••(pH)•
ANALOG OUTPUT PORT 1
4 MA =
X.X ( units )