OUMAN EH-203
Measurement 6: Pressure measurement
OUMAN EH-203
Ouman EH-203
Measurement
6
41
0 - 10V
24 VAC
Pressure
meas. transmitter
For example VPL10
1 k
Add series
and
shunt
resistor
1 k
0 - 10 V
24 VAC
(2 - 10 V)
Wind or pessure
meas. transmitter
Ouman EH-203
Measurement
6
41
bar
16
14
12
10
8
6
4
2
0
bar
16
14
12
10
8
6
4
2
0
Connection 2. Connect the pressure sensor without resistor
Verk.paine (bar)
Mittausalue
Ylärajahäl.
Täyttöhäl.
Alarajahäl.
16.0
2.2
0.7
0.5
If the pressure in the network never exceeds 50% of the emitter's
measurement area, the emitter can be connected directly to the controller
without voltage divider resistors. Set the measurement area at one half of
the emitters actual measurement area (e.g., 8.0 bar for a 0…
16 bar emitter). Without voltage divider resistors the controller only
recognizes one half (0…5V) of the emitter's measurement message
(0…10V).
Verk.paine (bar)
Mittausalue
Ylärajahäl.
Täyttöhäl.
Alarajahäl.
8.0
2.2
0.7
0.5
Verk.paine (bar)
Mittausalue
Ylärajahäl.
Täyttöhäl.
Alarajahäl.
8.0
2.2
0.7
0.5
31
Connection 1. Connect the pressure sensor using a resistor
0 1
2 3 4 5 6 7 8
9 10 V measurement message sent by the pressure transmitter
0 1
2 3 4 5 V
measurement message received by the controller
0 1
2 3 4 5 6 7 8
9 10 V
measurement message sent by the pressure transmitter
0
1
2
3
4
5 V
measurement message received by the controller
bar
16
14
12
10
8
6
4
2
0
The controller's measurement channel 6 can have a 10V emitter voltage but
can only measure 0…5V. If you want to use the entire measurement area of
a 0…10V emitter (e.g., 0…16 bar), make the connection using a voltage
divider resistor. The measurement area is then the emitter's measurement
area, e.g., 16 bar.
Network pressure:
NetworkPress(bar)
Meas.area
OverpressAl.
Fill alarm
LowerLimAl.
16.0
2.2
0.7
0.5
Set alarm limits for overpressure, fill, and lower limit alarms
Overpressure alarms
Fill alarm
Lower limit alarm:
: The controller gives an alarm when the pressure in
the network exceeds the “Upper Limit Alarm” setting. The factory setting is
2.2 bar. Typical reasons for upper limit alarms include; excessive filling of
the network, warning valve dysfunction or expansion tank breakage. Drain
excessive water from the network. Inspect the condition of the warning
valve and expansion tank if the alarm was not caused by overfilling.
: The controller gives an alarm when the pressure in the network
drops below the “FillAlarm” setting. The factory setting is 0.7 bar. The fill
alarm warns of underpressure in the network. In the event of an alarm,
check if any leaks can be seen. Fill the system to its normal pressure.
Check out the situation. If the fill alarm goes off frequently, check the
condition of the expansion tank and inspect it for possible leaks.
The controller gives an alarm when the pressure in the
network drops below the “Lower limit alarm” setting. The factory setting is
0.5 bar. The lower limit alarm is a critical warning of a too low pressure in
the network. Look for possible leaks. Inspect the condition of the
expansion tank. If the fill alarm and lower limit alarm occur in succession
within a short time period it is usually an indication of a leak in the network.
NetworkPress(bar)
Meas.area
OverpressAl.
Fill alarm
LowerLimAl .
8.0
2.2
0.7
0.5
Produal VPL10
pressure transmitter
NetworkPress(bar)
Meas.area
OverpressAl.
Fill alarm
LowerLimAl.
8.0
2.2
0.7
0.5
