ONICON F-2600 - Manual (Page 45)

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F-2600 & F-2700 Vortex Flow Meter Manual 02/15 - 0808-7 / 19204 Page 45
AC or DC powered meters
Freq Out +
Freq Out -
Freq. Out voltage = +V
Select resistor so that current
through Freq. Out ≤ 40 mA.
PWR
PWR
DC Powered meters only
Freq. Out voltage = + Power voltage for meter
Freq. Out +
Freq. Out -
R current limit ~10K
+
24 VDC Out
- 24 VDC Out
AC units only
Meter provided DC Power
Freq . Out +
Freq . Out -
Freq. Out voltage = + Power voltage for meter
R current limit ~10K
Figure 34. Isolated Frequency Output Using External Power Supply
Figure 35. Non-Isolated Frequency Output Using Input Power Supply
Figure 36. Isolated Frequency Output Using Meter Provided Power Supply
2.7.4 Pulse Output Connections
The pulse output is used for a remote counter. When the preset volume or mass (defined
in the totalizer settings, on page 62) has passed the meter, the output provides a 50
millisecond square pulse.
The pulse output optical relay is a normally-open single-pole relay. The relay has a
nominal 200 V / 160 ohm rating. This means that it has a nominal on-resistance of 160
ohms, and the largest voltage that it can withstand across the output terminals is 200 V.
However, there are current and power specifications that must be observed. The relay
can conduct a current up to 40 mA and can dissipate up to 320 mW. The relay output is
isolated from the meter electronics and power supply.
There are three connection options for the pulse output. The first had a separate power
supply (Figure 34). The second uses the flow meter power supply (Figure 35)
(DC powered units only), and the third uses the internal 24 VDC power supply (Figure
2-32)(AC powered units only). Use the first option with a separate power supply (5 to 36
VDC) if a specific voltage is needed for the pulse output. Use the second configuration
if the voltage at the flow meter power supply is an acceptable driver voltage for the load
connected. (Take into account that the current used by the pulse load comes from the
meter’s power supply). Use the third configuration if you have an AC powered unit
only. In any case, the voltage of the pulse output is the same as the voltage supplied to
the circuit.
DC powered meters only
AC units only
Meter provided DC power