VorTek Pro-T, Инструкция по эксплуатации

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Chapter 2 Installation Series M22/M23/M24 Instruction Manual
2-
30
M-000-00010
DC powered meters only
R
L
> 250 Ohm
DC Power
DC Common
mA Meter For HART
communications
the signal loop
must have a
minimum of 250
ohms load
resistance.
Figure 2-31. Non-Isolated 4 – 20 mA Output Using Meter Input Power Supply
AC units only
Meter Provided DC
Power
R
L
> 250 Ohm
24 VDC
24 VDC
For HART
communications
the signal loop
must have a
minimum of 250
ohms load
resistance.
mA Meter
Figure 2-32. Isolated 4 – 20 mA Output Using Meter Provided Power Supply
Frequency Output Connections
The frequency output is used for a remote counter. It can be scaled to out-
put a 1 to 10 kHz signal proportional to mass or volume flow, tempera-
ture, pressure or density.
The frequency output requires a separate 5 to 36 VDC power supply. The
frequency output optical relay is a normally-open single-pole relay. The
output can conduct a current up to 40 mA. It is isolated from the meter
electronics and power supply.
There are three connection options for the frequency output
– the first with a
separate power supply (Figure 2-33), the second using the flow meter power
supply (Figure 2-34)(DC powered units only), and the third using the inter-
nal 24 VDC power supply (Figure 2-35)(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 frequency output. Use the second configuration if the volt-
age at the flow meter power supply is an acceptable driver voltage for the
load connected. (Take into account that the current used by the frequency
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 frequen-
cy output is the same as the voltage supplied to the circuit.