5
3.0
CALIBRATING THE TRANSMITTER
Calibration Setup:
1.
Insert the reference RTD.
2.
Connect RTD simulator.
3.
Connect DMM monitor and power supply.
Figure 3-1. Calibration Setup (Resistance Source)
To calibrate the transmitter, follow these steps (refer to Figure 3-1):
1.
Locate the model number in Table 3-1 or 3-2 and set the resistance source to
the LO-IN value.
2.
Adjust the Zero potentiometer until the milliammeter reads 4.00 mA.
3.
Set the resistance source to the HI-IN value (in your appropriate table) and read
the output current on the milliammeter.
4.
Adjust the Span potentiometer to obtain the 20 mA on the milliammeter.
5.
Set the resistance source to LO-IN resistance. If the output current is not 4.00
mA, repeat steps 2 through 7.
6.
When calibration is complete, remove the transmitter from the setup.
1
2
3
4
5
ZS
RESISTANCE
SOURCE
DC SUPPLY
24 VDC
DMM
(4–20 mA)
MONITOR
(–)
(+)
(–)
(–)
(+)
(+)
COPPER
WIRE
250 Ohms
INPUT
RTD
WIRE
SPAN
ZERO