Rockwell Automation 1771-OFE/B Analog Output Module User Manual - Manual (Page 54)

MAX
6-2
Publication 1771Ć6.5.30 - November 1998
Preparation for Calibration -
1. Turn off the processor and I/O chassis power.
2. Remove the field wiring arm.
3. Remove the analog output module from the I/O chassis.
4. Remove the module covers.
5. Connect the backplane extender card (cat. no. 1771-EX) to the
circuit board.
6. Insert the extender card/circuit board assembly in the I/O chassis.
7. Reinstall the field wiring arm.
Important: If you have a spare or unused field wiring arm, you may
want to temporarily switch it with the module’s present
field wiring arm. You can use this spare arm for test
purposes in order to avoid disconnecting your analog
device wires.
Important: The accuracy of this calibration procedure is dependent
upon the precision of your load resistors. Use resistors
with a tolerance of 1.0%. You should be able to attain
voltage readings to +1mV. For greater accuracy, use
load resistors with tolerances less than 1.0%.
Use load resistors with values of 1K ohms. For greater accuracy,
you can substitute the 1K ohm resistor with a resistor that more
closely approximates your actual device load.
Calibration Procedure
1. Disconnect your analog device wires from the module’s field
wiring arm if you are not using a spare field wiring arm for
calibration.
2. Attach a resistor with a value of 1K or greater (to approximate
your actual load) across Channel 1 (the top two screws in
Figure 6.1) of the field wiring arm.
3. Attach three more 1K resistors across the remaining three
channels on the field wiring arm just as you did in Step 2
(Figure 6.1).
4. Place the LAST STATE configuration jumpers (Figure 6.2) in the
MAX position (if they are not there already).
5. Select the +10V output range by placing the four channel
configuration jumpers in the position shown in Figure 6.2.
Voltage Output Version
(1771ĆOFE1)