Meriam M334 4-20 Milliamp Loop Calibrator - Manual (Page 4)

2 Wire mA, 2 Wire % (Percent of 4 to 20 mA)
Choose this function to simulate a 2 Wire Transmitter output from 0.00 to 24.00 milliamps. Operates
in loops with power supply voltages from 2 to 100 VDC
mA OUT, % OUT (Percent of 4 to 20 mA)
Choose this function to simultaneously supply power to a 2 Wire Transmitter while displaying the 4
to 20 mA output of the transmitter.
1) Disconnect one or both input wires from
the device to be calibrated.
2) Select “mA” or “% 4 to 20mA” with slide
switch q .
3) Select “SOURCE” using slide switch w .
4) Turn the knob r clockwise several times
until full scale output (24.00 mA/125.0%)
is obtained (this can be verified by clipping
the output leads together and checking
that the display indicates
“FULL SCALE”).
5) Connect the red source lead of the Meriam
Model M334 to the plus (+) input of the
device and the black source lead to the
minus (-).
The Meriam Model M334 supplies a nominal 24 volts DC at 24 mA to the 2 Wire Transmitter. The
current passed by the transmitter will be accurately displayed by the Meriam Model M334. Calibrate
the transmitter in the usual manner and disconnect the Meriam Model M334.
Simulate 2-Wire Transmitters
Power & Measure 2-Wire Transmitters
To
Sensor
M334
mA Loop
Calibrator
Typical
2-Wire
Transmitter
(Disconnected)
+ IN - REF +OUT-
Receiver
Powers External
2-Wire Transmitter
Power Supply
(2 to 100 VDC)
8.00 2 WIRE
mA
M334
mA Loop
Calibrator
Typical
2-Wire
Transmitter
+ IN - REF +OUT- Transmitter Input
Sensor
Process Signal
Simulated Input
25.4 OUT
%
1) Disconnect one or both input
wires from the device to be cali-
brated.
2) Select “mA” or “% 4 to 20mA”
with slide switch q .
3) Select “2 WIRE” using slide
switch w .
4) Connect the red input lead of the
Meriam Model M334 to the plus
(+) input of the field connections
and the black lead to the minus
(-).
Loop current is adjusted by turning
knob
r while the EZ-CHECK™
switch e is in the “DIAL” position,
or the current can be set at the fixed
points of 4.00mA (0.0%) or 20.00mA
(100.0%) with switch
e .
Meriam Process Technologies
10920 Madison Ave. • Cleveland, OH 44102 Tel: 216.281.1100 • Fax: 216.281.0228 • [email protected] • www.meriam.com