37/69
Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
13 Functional readiness and faults
15.10.2002
13 Functional readiness and faults
The RVW26… conducts a number of tests at regular intervals:
·
Checking the input signals (permissible combinations, valid range, etc.)
·
Internal tests (checking both hardware and software)
In the event of fault, the following actions will be triggered:
a) Fault
in
operation
«Q4...Q5» opens
and shuts the burner down,
«Q4 - H» closes,
thus indicating
«Error»
.
The unit's display shows a
flashing error code
(refer to section «Table of error
codes»).
If several faults occur at the same time, the individual error codes change cyclically.
If the handheld terminal is connected, its display shows the respective
error message
in clear text.
The RVW26… initiates lockout and must be reactivated by making a reset or by using
the handheld terminal.
b) Fault in programming mode
Same as under a), but the display of the handheld terminal only shows an «E» in the
first column of the fourth line.
The parameters can still be set, however.
The error message can be displayed in clear text by changing to programming level
«F» (fault protocol).
The RVW26... is reset by switching the power supply off.
Readiness contact «Q4 - Q5» closes after about 2 seconds and «Q4 - H» opens.
In programming mode, it is also possible to make a reset by executing command
«ClrErro» on programming level 7.
Exception:
If parameters are set outside the permissible range, the RVW26… will deliver an error
message as described above.
That fault will automatically disappear when the respective parameter is changed back
to within the permissible range.
Resetting a fault
(reset)