Teledyne 4220 Installation And Operation Manual page 63

The flow meter's internal resolution and its accuracy are based
on the value you enter for Maximum Head. The flow meter will
display:
FLOW RATE AT MAXIMUM HEAD
X.XXX CFS (or other units of measure)
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.
DATA TYPE FOR ANALOG OUTPUT 1
• (OFF)••(LEVEL)••(FLOW RATE)••(VELOCITY)••(pH)•
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:
ANALOG OUTPUT PORT 1
4 MA = X.X (units)
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
or C for temperature, mg./l for dissolved oxygen, etc. After you
have set the minimum value for the port, the flow meter will
request you to enter a value for full-scale, or 100%:
ANALOG OUTPUT PORT 1
20 MA = X.X (units)
This value causes the port to transmit 100% or 20 mA. For
example if the data type selected for this output were level, and
the unit is measuring level in a four-foot pipe, you would enter a
full-scale value of four feet. If the actual level reading is cur-
rently two feet, the analog output would read 12 mA (50% if the
4-20mA current range is selected) or 10 mA (50% if the 0-20 mA
4220 Flow Meter
Section 2 Programming
2-35