Watlow CAS200 - Manual (Page 88)

Chapter 5: Troubleshooting and Reconfiguring CAS200 User’s Guide
76 Watlow Anafaze
Testing Digital Inputs
1. Turn off power to the scanner.
2. Disconnect any system wiring from the input to be
tested.
3. Restore power to the scanner.
4. Go to the DIGITAL INPUTS parameter in the MANUAL
I/O TEST
menu. This parameter shows whether the
digital inputs are H (high, or open) or L (low, or closed).
5. Attach a wire to the terminal of the digital input to
test. When the wire is connected only to the digital in-
put terminal, the DIGITAL INPUTS parameter should
show that the input is H (high). When you connect the
other end of the wire to scanner common (TB50 termi-
nal 3), the DIGITAL INPUTS parameter should show
that the input is L (low).
Additional Troubleshooting for Computer
Supervised Systems
These four elements must work properly in a computer-
supervised system:
• The scanner
• The computer and its EIA/TIA-232 or EIA/TIA-485
serial interface
• The EIA/TIA-232 or EIA/TIA-485 communication
lines
• The computer software
For troubleshooting, disconnect the communications line
from the computer and follow the troubleshooting steps in
the first section of this chapter. The next few sections
explain troubleshooting for the other elements of computer
supervised systems.
Computer Problems
If you are having computer or serial interface problems,
check the following:
• Check your software manual and make sure your
computer meets the software and system
requirements.
• Check the communications interface, cables, and
connections. Make sure the serial interface is set
according to the manufacturer’s instructions.