Micro Motion Fisher Rosemount RFT9739, Инструкция по эксплуатации

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32
RFT9739 Rack-Mount Transmitter Instruction Manual
Output Wiring
continued
Configuration for constant
current Applications with high capacitance loading will benefit by wiring the
frequency/pulse output circuit to maintain a constant current source of
50 mA for any load between 0 and 220 ohms. This configuration renders
the control output circuit inoperable, and could affect the optocoupler
and dual-channel frequency outputs.
For constant current, add a jumper across terminals CN2-Z26 and
CN-D24, and a 100 to 250 ohm resistor at the PLC or pulse-counter end
of the cable, as illustrated in Figure 5-7.
The control output can be reconfigured to function properly, independent
of this frequency/pulse wiring procedure. See "Control output in open
collector mode," page 41.
The optocoupler and dual-channel frequency outputs could be affected
by configuring the frequency/pulse output for constant current as
described above. To reduce this risk, use a 250 ohm resistor, as
indicated in Figure 5-7.
Figure 5-7.
Frequency/pulse output
wiring for constant current
CAUTION
Adding a jumper across terminals CN2-Z26 and
CN2-D24 renders the control output circuit inoperable.
Do not attempt to use the control output circuit after you
add a jumper across terminals CN2-Z26 and CN2-D24.
RFT9739
output terminals
PLC
or
pulse counter
FREQ+ (signal line)
RETURN (ground)
100 to 250 ohm resistor
(see note)
To use the dual-channel frequency output or the optocoupler output
with this configuration, use only a 250 ohm resistor.