TROUBLESHOOTING
44
test fails the second time, return the counter for
repair.
Watch Dog Timer (1.3 Seconds) - Test #6
While the control is operating, an internal Watch
Dog Timer is incremented every millisecond.
Under normal operation, the control automatically
resets the Watch Dog Timer at least once per sec-
ond. If the control would malfunction during opera-
tion, the Watch Dog Timer may time out
(depending on the type of malfunction) and an
error code of “6” flashes on the display. If this type
of failure occurs, run the diagnostics using Func-
tion 40. Excessive electrical interference may
cause this type of failure without damage to the
control or the operating characteristics. If the diag-
nostics find no other fault, it is reasonable to
assume that the control is fully operational, unless
this failure is recurring.
OPERATION OF DIAGNOSTICS
When power is applied, the control begins by per-
forming tests #1, #2, #3 and #5. If all of these
pass, the counter is ready to operate as indicated
by flashing the count value on the display at one
half second intervals for four seconds, then
remaining lit.
To select the self-diagnostic mode, specify Func-
tion code 40 and enter a value of “1”. The control
immediately turns on all display segments and
LED indicators for 2 seconds. Then the displays
blank and the control steps through all five tests. If
all five pass, the control begins a display and LED
test routine. This routine sequences through flash-
ing the numbers “0” through “9” on the displays,
alternates the Preset 1, Preset 2 and Count LED
indicators and moving the decimal point from digit
to digit. When the display sequence is finished, the
control shows the count value and the Count indi-
cator is lit.
NOTE
The self-diagnostics should not be per-
formed while the process being controlled
is running. The control responds to count
pulses but ignores any incoming control
signals while the diagnostics are
operating.
Performing the diagnostic routines does not affect
the Function code parameters. Thus, when the
diagnostics are finished, the control retains all of
the operational characteristics previously pro-
grammed.
WHAT TO DO IF THE CONTROL FAILS A
DIAGNOSTIC TEST
If the control flashes a single digit number continu-
ously on power-up or when the self-diagnostics
are performed, it indicates which one of the tests
has failed. When the number displayed is “4”, “5”,
or “6”, the control can be allowed to operate by
pressing the FUNCTION key to clear the display.
,
,
,
,
WARNING
RUNNING THE COUNTER AFTER A
FAILURE HAS BEEN DETECTED CRE-
ATES A SERIOUS RISK TO THE OPER-
ATOR AND/OR MACHINERY.
As a minimum safety precaution, the Function
code Default mode (Function 43) should be
selected (enter a value of “1”) and the Function
codes reprogrammed. This will insure that the fail-
ure has not altered any of the operating character-
istics of the counter. Selecting the default
parameters with Function 43 also performs the
power-up self test, which could give another failure
indication (for tests #1, #2 or #3). If this occurs,
return the control for repair immediately.
Address units to be repaired to:
Cutler Hammer-Eaton Corporation
Durant Instruments
901 South 12th Street
Watertown, WI 53094
ATTENTION: REPAIR DEPARTMENT