MS574 0210 0007
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SENSOR SUPPLY
Terminal 3: sensor supply 1.2V, 3.2V
Terminal 3 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).
Terminal 4-5: POWER SUPPLY UNIT
To power the unit an internal battery can be used and / or an external DC power supply
of 16-30V DC.
Connect the "
-
" to terminal 4 and the "
+
" to terminal 5. When power is applied to these terminals, the
optional internal battery will be disabled / enabled automatically to extend the battery life time.
Terminal 6: Power supply: 8.2V sensor supply
With this option, a limited power supply for the sensor is available, for example to power a Namur
sensor. It offers 8.2V DC (max. 5mA).
REMARKS: TERMINAL CONNECTORS
TERMINALS 1-3; FLOWMETER INPUT
Two types of flowmeter signals can be connected to the unit: NPN and Reed switch. The screen of
the signal wire must be connected to the common ground terminal
The input signal type has to be selected with the correct SETUP-function (read par. 3.2.3.)
Pulse-signal NPN / NPN-LP input
The ER is suitable for use with flowmeters which have a NPN output signal. For reliable pulse
detection, the pulse amplitude has to go below 1.2V. Signal setting NPN-LP employs a low-pass
signal noise filter, which limits the maximum input frequency - read par. 3.2.3.
Flowmeter
INTERNAL
EXTERNAL
NPN signal input
2
Common ground unit
SIGNAL
1
GND
shielding
low-pass filter
selection NPN-LP
6
Option 8.2V DC
+ 3.2V DC
100K
