Watlow SDAC - Manual (Page 3)

Setup and Operation
Using the Serial DAC with a Controller
Complete the following steps to set up your Serial
DAC:
1. Check the Output Select jumpers on the Serial
DAC. Make sure that both jumpers are set for
either voltage or current.
2. In the controller menus:
• Set the output type to SDAC (Serial DAC).
• Select the Serial DAC signal type: Voltage or
Current.
• Set the desired high and low output signal val-
ues.
The exact parameter names vary depending on the
controller. See your controller manual.
Testing the Serial DAC
1. In the controller, select the loop to be tested.
2. Set the control output to manual mode.
3. Set a percent output level.
4. Use a volt or current meter to verify the output
level of the Serial DAC.
Troubleshooting
The following section contains troubleshooting infor-
mation for the Serial DAC.
Check the following first:
• Are the controller and Serial DAC wired and con-
figured correctly?
• Are the inputs to the controller, such as thermocou-
ples and RTDs, installed and working correctly?
Green Light on Serial DAC Does Not Light
Use a voltmeter to check:
• 5V power is present at the Serial DAC.
• Power is present at the controller.
Also, check data and clock line wiring, and make sure
that the controller’s output type is set to Serial DAC
for that loop.
Erratic and Incorrect Output Level
Check for reversed data and clock lines.
Output Level Incorrect, or No Output
• Check current and voltage jumper settings on the
Serial DAC.
• Check the controller’s voltage or current low and
high output level settings.
• Make sure the Serial DAC data input is wired to
the correct loop output.
Calibration Procedure
The standard Serial DAC is calibrated for precision
voltage output. To recalibrate your Serial DAC to out-
put currents with 0.1% accuracy, follow these steps:
NOTE
This procedure should be performed only by a technician famil-
iar with calibrating electronic equipment. The voltage or cur-
rent meter used should have the appropriate precision and be
properly calibrated.
1. Remove the two plug-in terminals.
2. Unscrew either end panel.
3. Gently slide the card out.
4. Reinstall the plug-in terminals:
5. Recalibrate the circuit:
a. Connect the voltage or current meter to the out-
put.
b. Connect the Serial DAC to the controller.
c. Set the controller’s output to Manual Mode, 0%
Output.
d. Adjust the control labeled “zero” to get the
desired output — typically 4.000 mA for current
outputs.
e. Set the controller’s output to 100% output.
Adjust the control labeled “span” to get the
desired full scale output (typically 20.000 mA).
f. Repeat steps c through f until you have
achieved the desired accuracy.
6. Remove the plug-in terminal blocks from the
Serial DAC.
7. Gently slide the card back into the appropriate
casing slot.
8. Screw on the end panel.
9. Replace the plug-in terminal.
Specifications
Watlow Anafaze offers a Serial DAC for precision
open-loop control. The Serial DAC is jumper selectable
for a voltage or current output. Multiple Serial DAC
modules can be used with one controller.
The Serial DAC carries the CE mark.
Table 1. Serial DAC Environmental Specifications
Storage Temperature -20 to 60°C (-4 to 140°F)
Operating Temperature 0 to 50°C (32 to 122°F)
Humidity 10 to 95%, non-condensing
WATLOW SDAC User’s Guide 3