HF131PEN_v0501_05
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4.4.2.
VOLTAGE SELECTION SENSOR SUPPLY
For Intrinsically Safe applications: read chapter 5.
Battery powered and output loop-powered applications:
Terminal 11 provides a limited supply voltage of 3.2 V DC (coil signals 1.2V) for the signal output of
the flowmeter.
Note:
This voltage MAY NOT be used to power the flowmeters electronics, converters etc, as it will
not provide adequate sustained power ! All energy used by the flowmeters pick-up will directly
influence the battery life-time. it is strongly advised to use a "zero power" pickup such as a coil or
reed-switch when operating without external power. It is possible to use some low power NPN or
PNP output signals, but the battery life time will be significantly reduced. (consult your distributor)
Option PD / PF / PM: Sensor supply: 3.2V - 8.2V - 12V or 24 V:
With this option, a real power supply for the sensor is available. The flowmeter can be powered with
8.2 - 12 or 24 V DC (max. 50mA@24V). The voltage is selected by the three switches inside the
enclosure.
Warning: be sure that all the leads to the terminals are disconnected from the unit when
the internal plastic protection cover has been removed !
HIGH VOLTAGE 400V !! NEVER connect the mains power supply to the unit when the
plastic protection cover has been removed !!!
First, remove the terminal strip(s) after which the internal plastic cover can be removed. The
switches are located in the top left corner (option PD) or on the right hand (option PM) as indicated:
Fig. 10: switch position voltage selection (option PD / PF / PM).
Switch positions
SENSOR
A
SENSOR
B
VOLTAGE SELECTION
SWITCH
1
VOLTAGE
SWITCH
2
VOLTAGE
SWITCH
3
SWITCH
4
VOLTAGE
internal
3.2 V DC
internal
3.2 V DC
on
on
8.2 V DC
external switch
3+4 external switch
3+4 off
on 12
V
DC
on
off 12
V
DC
off
off 23
V
DC
Function switch 1:
voltage selection sensor A - terminal 11.
Function switch 2:
not available for this Model.
Function switch 3+4:
the combination of these switches determine the voltage as indicated.
If switch 1 and 2 are both set to position OFF than the selected voltage with
switch 3+4 is valid for both sensors.
