Siemens LMV 5 Series, Технические инструкции, Страница: 186 / 374

Technical Instructions LMV Series
Document No. LV5 ‐ 1000
Section 6 Page 14 SCC Inc.
Suggested O
2
Trim Commissioning ‐ Premix Mesh Burner or Nozzle Mixing Burner with High
Percentage of FGR (Typically LMV52.440)
1. The commissioning procedure assumes the following:
a. All Pre ‐ Requisites for an LMV52 system with O
2
trim (and VSD if equipped) have been met
according to Section 4 of this literature.
b. The Ratio Control Curves have been commissioned according to Section 4 of this literature.
c. Section 6 of this literature has been read and understood up to this point.
d. If a start mode with combustion air temperature compensation will be used, the air
temperature sensor must be installed and activated.
2. As was the case for the Ratio Control Curves in Section 4, the same free spreadsheet can also be
used to assist in the commissioning of the O
2
trim. This spreadsheet graphically illustrates the O
2
curves as well as provides an orderly way to record the details of how the burner was set up.
Figure 6 ‐ 3: LMVx Curves Spreadsheet
3. The key to commissioning the O
2
curves quickly and easily is contained in the Ratio Control Curves.
Specifically, the following must be achieved for each point on the Ratio Control Curves (as
paraphrased from Section 4 of this literature):
a. Safe combustion as verified by a calibrated stack gas analyzer
b. The % load matching the fuel flow within +/ ‐ 3%
c. Emissions compliance
d. Smooth Ratio Control Curves (no sharp peaks or valleys)
e. VSD speed should increase with load in a linear fashion (if equipped)
f. Determine the %O
2
wet corresponding to the fuel rich limit (O
2
Alarm value) for each point.
Probing may or may not be possible depending on the burner design. Also, follow burner OEM
recommendations. Most mesh burner elements can be damaged if run too fuel rich.*
g. Find and record the %O
2
wet corresponding to the fuel lean limit ( O2 MaxValue ) for Point 1 and
Point 10 by probing or according to burner OEM recommendations.*
h. Find the target %O
2
. For these burners the target %O
2
for each point will be the %O
2
wet
corresponding to emissions compliance (typically CO, NOx). After the target %O
2
is found,
increase the %O
2
and leave the point at least 0.5% O
2
leaner than the target %O
2
. Record this as
the "saved" value for each curve point.
HOME