HF127PEN_EL_TA_v0501_04
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B - ANALOG OUTPUT
A linear 4-20mA signal (option AB: 0-20mA or option AU: 0-10V) output signal is generated
according to the calculated flowrate with a 10 bits resolution. The settings for flowrate (SETUP - 2)
directly influence the analog output.
Note:
When the analog output is not used, please make sure that setting B1 is disabled, or else the
battery life time will be reduced significantly!
When a power supply is available but the output is disabled, a 3.5mA signal will be generated.
The relationship between rate and analog output is set with the following functions:
DISABLE / ENABLE
B1
The D/A converter has a relatively high power consumption. If the analog
output is not being used, select “disable” to switch-off the converter.
For more information read par. 4.4.3.
MINIMUM FLOWRATE
B2
Enter here the flowrate at which the output should generate a 4mA signal
(or 0mA / 0V) - in most applications at flowrate “zero”.
The number of decimals displayed depend upon SETUP 23.
The time and measuring units (L/min for example) are dependant upon
SETUP 21 and 22 but are not displayed.
MAXIMUM FLOWRATE
B3
Enter here the flowrate at which the output should generate a 20mA (or
10V) - in most applications at maximum flow.
The number of decimals displayed depend upon SETUP 23.
The time and measuring units (L/min for example) are dependant upon
SETUP 21 and 22 but can not be displayed.
CUT-OFF
B4
To ignore leakage of the flow for example, a low flow cut-off can be set as
a percentage of the full range of 16mA (or 20mA / 10V). When the flow is
less than the required rate, the current will be 4mA.
Examples:
4
M
A
(SETUP B2)
20
M
A
(SETUP B3)
C
UT
-
OFF
(SETUP B4)
R
EQUIRED RATE
O
UTPUT
0 L/min
100 L/min
2%
(100-0)*2% = 2.0 L/min
4+(16*2%) = 4.32mA
20 L/min
800 L/min
3.5%
(800-20)*3.5%= 27.3 L/min
4+(16*3.5%)=4.56mA
TUNE MIN / 4MA
B5
The initial minimum analog output value is 4mA (or 0mA / 0V). However,
this value might differ slightly due to external influences such as
temperature for example. The 4mA value (or 0mA / 0V) can be tuned
precisely with this setting.
Before tuning the signal, be sure that the analog signal is not
being used for any application!
After pressing PROG, the current will be about 4mA (or 0mA / 0V). The
current can be increased/decreased with the arrow-keys and is directly
active.
Press ENTER to store the new value.
TUNE MAX / 20MA
B6
The initial maximum analog output value is 20mA (or 10V). However, this
value might differ slightly due to external influences such as temperature
for example. The 20mA value (or 10V) can be tuned precisely with this
setting.
Before tuning the signal, be sure that the analog signal is not
being used for any application!
After pressing PROG, the current will be about 20mA. The current can be
increased/decreased with the arrow-keys and is directly active. Press
ENTER to store the new value.
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