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Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
15 Programming the RVW26...
15.10.2002
Curve characteristic
5
S e t
L o a d
^
2 5 .
0
9
1
A u x 1 P o s
:
1 .
2 4
A u x 2 P o s
:
1 .
8 8
For both types of fuel, a specific load / position curve can be programmed.
The coarse setting of the different curves for «Aux1« and «Aux2» can be made with the
5 or 9 breakpoints (programming level 4).
Here, various error messages can occur near the end switch positions.
To rectify the causes, the curves must be moved into the permissible range using mode
«17 points».
The fine adjustment is then made in the position «17 breakpoints».
Now,
no
change should be made back to a lower number of breakpoints since the
manually set values will be overwritten, due to automatic calculation of the intermediate
points.
When the burner is in operation, the curves of the RVW25... and RVW26... should be
optimized at the same time if possible.
For that purpose, 2 AZW20.20 (1 for the RVW25... and 1 for the RVW26...) or a
changeover switch KF8879 are required.
To ensure a correct link of the actuators, the RVW26... follows the load signal of the
RVW25... in programming mode also.
To optimize a curvepoint, it must be approached with the RVW25... (e.g. with the help
of an AZW20.20) and can only then be correctly set with the RVW26...
If the breakpoint lies outside the load limits, the actuators will be driven to the positions
of the load limits.
At least one point must be programmed outside each load limit.
Parameter
Meaning
SetLoad
Burner output at the respective curvepoint
Setting range:
0...100 %
Increment:
SetPts = 5
25 % = coarse setting
SetPts = 9
12.5 % = coarse setting
SetPts = 17
6.25 % = fine-tuning
The increments depend on the number of curvepoints selected on programming
level 4.
Aux1Pos
Position of auxiliary actuator 1
Setting range:
end switch_ end switch_tol hysteresis
end switch_open – end switch_tolerance
Increment:
0.04 V
Factory setting:
0 V
Aux2Pos
Position of auxiliary actuator 2
Setting range:
end switch_ end switch_tol hysteresis
end switch_open – end switch_tolerance
Increment:
0.04 V
Factory setting:
0 V
Programming level 5
Display
Interpretation
