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Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
18 Notes on the commissioning of a burner
15.10.2002
·
On programming level 6, set the ignition load and ignition positions.
Then, on
programming level 7, store the set parameters with «SavePar» in the RZD20 and
cancel the fault messages. When changing from programming mode to operating
mode, an automatic interpolation with 17 curvepoints is always made. Missing cur-
vepoints will automatically be calculated by the RVW26...
·
Start the burner.
To do this, quit the programming mode (change 0 on the pro-
gramming level). When the burner is in operation (RVW26... in phase «R»), it is
possible to change back to the programming mode, allowing the burner settings to
be optimized on programming level 5
1
2
3
4
5
Burner
output %
0
25
50
75
100
Oil throughput
kg / h
78731d05e/1001
90
80
60
40
20
0
Curve-
point
Fig. 29
Graph for adjustment of the curve
For example:
A burner for light oil has a capacity of 1 MW.
This output requires an oil throughput of 90 kg / h.
With the help of a graph, the required oil throughput can be ascertained for each curve-
point.
At each curvepoint, the fuel actuator is now to be set for the respective amount of fuel.
Then, the air damper actuator is to be set to produce the required amount of excess air
(e.g. with CO
2
, O
2
or CO measurements).
The setting should be made such that the actual burner output corresponds to the dis-
play of the RVW26...
When used in connection with O
2
trim control, this burner setting must be made with
sufficient amounts of excess air
.
Take into account that application of a correcting variable (O
2
) will reduce the amount
of excess air to the optimum level.
But the excess air volume can never become greater than the burner’s basic setting.
·
Make optimum ignition settings on the programming level
·
When using 2 types of fuel, change to the second fuel now (terminals «F1 / F2»)
and make the above settings for the second fuel also
·
In the case of a plant with O
2
trim control, start the plant and set the «Disturb»
factor such that the RVW25... and RVW26… will be able to compensate all effects
(supply air temperature, calorific value, etc.).
