Endress+Hauser Proline Prosonic Flow 93 Function Manual page 71

Device functions Proline Prosonic Flow 93
Endress+Hauser
➞
OUTPUTS PULSE/FREQUENCY OUTPUT (1...2)
OUTPUT SIGNAL
!
(4207)
Function is not available unless the FREQUENCY setting was selected in the
OPERATING MODE (4200) function.
For selecting the output configuration of the frequency output.
Options:
0 = PASSIVE - POSITIVE
1 = PASSIVE - NEGATIVE
2 = ACTIVE - POSITIVE
3 = ACTIVE - NEGATIVE
Factory setting: PASSIVE - POSITIVE
Explanation
• PASSIVE = power is supplied to the frequency output by means of an external power
• ACTIVE = power is supplied to the frequency output by means of the device-internal
Configuring the output signal level (POSITIVE or NEGATIVE) determines the quiescent
behaviour (at zero flow) of the frequency output.
The internal transistor is activated as follows:
• If POSITIVE is selected, the internal transistor is activated with a positive signal level.
• If NEGATIVE is selected, the internal transistor is activated with a negative signal
!
With the passive output configuration, the output signal levels of the frequency output
depend on the external circuit (see examples).
Example for passive output circuit (PASSIVE)
If PASSIVE is selected, the frequency output is configured as an open collector.
m
!
For continuous currents up to 25 mA (I
Example for output configuration PASSIVE-POSITIVE:
Output configuration with an external pull-up resistance.
In the quiescent state (at zero flow), the output signal level at the terminals is 0 V.
m
o
p
In the operating status (flow present), the output signal level changes from 0 V to a
positive voltage level.
(continued on next page)
Functional description
➞
CONFIGURATION (GENERAL/FREQUENCY)
Note!
supply.
power supply.
level (0 V).
Note!
➀
n
= Open Collector, = External power supply
Note!
U (V)
m
o
t
n
= Open Collector, = Pull-Up-Resistance
= Transistor activation in "POSITIVE" quiescent state (at zero flow)
= Output signal level in quiescent state (at zero flow)
U (V)
7 Block OUTPUTS
1 5 7
8 3
+
➁
=
U = 30 V DC
max
-
= 250 mA / 20 ms).
max
+ U = 30 V DC
max
n
U (V)
p
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t
F06-xxxxxxxx-04-xx-xx-xx-004
A0001225
t
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