Instruction manual

Output Wiring
continued
RFT9739 Field-Mount Transmitter Instruction Manual 45
Output Wiring Startup TroubleshootingBefore You Begin Getting Started Mounting
Power-Supply and
Sensor Wiring
If the pressure transmitter requires a power supply less than or
equal to 11.75 V,
the RFT9739 can power the pressure transmitter. Use
RFT9739 terminals P and S. Terminal P (MA PWR OUT) is the power
output to the pressure transmitter, and terminal S (MA SIG IN) is the
signal input to the RFT9739, as shown in
Figure 5-20a
.
If the pressure transmitter requires a power supply greater than
11.75 V,
or if other loop devices are required, an external source can
power the pressure transmitter. Use RFT9739 terminals S and 23.
Terminal S (MA SIG IN) is the signal input to the RFT9739, and terminal
23 (SIGNAL GND) is the return, as shown in
Figure 5-20b
.
If digital communication between the pressure transmitter and the
RFT9739 is required,
use RFT9739 terminals 17 (PV+) and 18 (PV–),
as shown in
Figure 5-20c
, page 46.
Figure 5-20a. Wiring to pressure transmitter — analog input
Figure 5-20b. Wiring to pressure transmitter — external power, analog input
Pressure
transmitter
WARNING: Pressure transmitter wiring is
not intrinsically safe
RFT9739
output terminals
Pressure
transmitter
WARNING: Pressure transmitter wiring is
not intrinsically safe
Power
supply
24 VDC
4-20 mA
Optional
loop device(s)
RFT9739
output terminals
Terminal 23 must be connected directly to the
negative (–) terminal of the external power supply.