Virginia Controls, LLC
MH-3000 User Manual, 1_03C10-VC
Page 105
example above, the CPU is attempting to communicate with boards 1, 2, and 3. Board 3 is
communicating properly, but boards 1 and 2 are
not. The “*” in the example above indicate
numbers that are changing quickly.
Address 051E counts the number of failed IO board communication attempts. This
should be 0, as shown in the sample below. (Address 051C is 2E, address 051D is E0 and
address 051E is 00)
051C 2E E0 00 00
0520 00 00 00 00
If there are intermittent problems, such as noise causing communication errors, then this
value will gradually increase. Check the addressing of the boards, and that all cables are
fitted properly. Also check the grounding of the controller. See the section Show Internal
Memory for instructions on viewing internal memory addresses.
9.2
I/O Board Replacement
WARNING: When replacing a board, the Address Switch setting on the
new board must be set to match the old board.
To replace an I/O board, TURN THE POWER OFF. Unplug all the terminal blocks at the
top and bottom of the board. Unplug the Power Connector and the I/O Bus Connectors.
Remove the screws holding the board in place. Install the new module by reversing the
above steps.
9.3
Factory Assistance
IMPORTANT: IF TROUBLESHOOTING ASSISTANCE IS REQUIRED FROM VIRGINIA
CONTROLS, GET THE FOLLOWING INFORMATION BEFORE CALLING (ADDITIONAL
TROUBLESHOOTING INSTRUCTIONS MAY BE GIVEN, DEPENDING ON THE NATURE OF THE
PROBLEM):
•
THE VIRGINIA CONTROLS DRAWING NUMBER
(located at the bottom right of the
schematic).
•
AN EXACT DESCRIPTION OF THE PROBLEM.
•
THE STATUS OF ALL THE INPUT AND OUTPUT POINTS.
•
THE STATUS OF THE LIGHTS ON THE CPU.
9.4
Changes for Program Revisions
The following section lists the changes that are included in program revision.
9.4.1
Program Revision 2D
Approximate Date of implementation
–
10/16/2003