41/69
Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
14 Error codes and rectification of faults
15.10.2002
If these faults occur repeatedly, the fault may be caused by electromagnetic fields and /
or line-related faults generated for instance by powerful radio transmitters, variable
speed drives, welding machines, etc.
Remedy:
Take action at the source of the problem, use EMC filters.
These faults can also occur if the transfer resistance of the potentiometer exceeds a
certain level, caused for instance by dirt or local welding.
This is the case when the problem always occurs in the same potentiometer position.
Remedy:
Replace the potentiometer.
These faults can also occur when there are inadmissible hum voltages on the potenti-
ometer lines.
Remedy:
Check shielding of the lines to the feedback potentiometers (screen may at
no point be connected to «PE»).
These faults can occur when the actuator running time on programming level 1 is incor-
rectly set.
For examples of determining the running time, refer to «Programming
the RVW26…»!
These faults can also occur if the shielding of the potentiometer lines is not correctly
connected.
Remedy:
Check shielding of the lines to the feedback potentiometers.
Error code
displayed by
the unit
Text displayed
by the hand-
held terminal
Hints on the cause of the fault
Hints on troubleshooting
-30
lin ad-convert
-31
superpos load
-32
superpos aux1
-33
superpos aux2
-34
pos contr load
-35
pos contr aux1
-36
pos contr aux2
-37
disturb check
-38
controll rel 1
-39
controll rel 2
-40
line input-bit
-41
supply voltage
-42
2
nd
contr rel 1
-43
under voltage
-44
CPU error
-45
RAM error
-46
ROM error
-47
undef interrup
-48
value conf reg
-49
range Bx_0V
-50
range Bx_10V
-51
range NBx_10V
-52
range U_5V
-53
range UT_x
-54
fuel changed
-55
process timing
These are faults the RVW26… has detected
when testing its software and hardware.
Reset the RVW26...
·
If the fault occurs sporadically, it may be
caused by EMC problems. In that case, the
source of the problem must be identified
and the wiring checked
·
Are the cables to the feedback potenti-
ometers screened and is the screen con-
nected exclusively to the ground of the
RVW26... (terminal «M»)
*
?
The screen may never be connected to
«PE»!
·
The cables to terminals «X1» and «X2»
must also be screened
·
If the fault occurs again after a short period
of time and if electromagnetic interference
can be excluded, the RVW26... must be
replaced
Notes on errors -05
through -07
Notes on errors -22
through -29 and -32
through -36
Notes on errors -22
through -23 and -28
through -29
