Practical Instrument Electronics 850 - Manual (Page 20)

Page 18
Pr
eliminar
y
Typical
2-Wire
Transmitter
+ IN - REF +OUT-
Transmitter Input
Sensor
Process Signal
Simulated Input
SOURCE
HI
SET
LO
MAX
READ
MIN
READ
11.999
mA
PWRM 5 6 + -
Power/Measure mA, Power/Measure % (Percent of 4-20 or
10-50 mA)
Choose this function to simultaneously supply power to a 2 Wire
Transmitter while displaying the 4.000 to 20.000/10.000 to
50.000 mA output of the transmitter.
Move the power switch w to READ then Double Click the
EZ-DIAL knob to get into the Menu. Turn the knob e to scroll
through the settings and press the knob to make your selection.
Select mA for the FUNCTION and PWR MEAS for the MODE.
Choose either mA or % and whether you need the 250
Ω HART
resistor active in the loop (250Ω resistor is only available in
4-20mA operation).
Disconnect one or both input wires from the device to be
calibrated. Connect the red source lead of the PIE 850 to the
plus (+) input of the device and the black source lead to the
minus (-).
The PIE 850 supplies a nominal 24 volts DC at 24 mA or 40 volts
DC at 52 mA to the 2 Wire Transmitter. The current passed by
the transmitter will be accurately displayed by the PIE 850.
Calibrate the transmitter in the usual manner and disconnect the
PIE 850. Signals above 24 or 52 mA are current limited by
protection circuitry with “OVERRANGE” flashed on the display
and the red OVERLOAD LED lit.