MQ Power WHISPERWATT DCA125SSIU4F Operation Manual page 57

EMISSION CONTROL
The emission control system employed with the Isuzu
BR-4HK1X diesel engine consists of a Diesel Oxidation
Catalyst (DOC).
This device oxidizes large amounts of harmful nitrogen
oxides (NOx) and particulate matter (PM) which are emitted
by diesel engines. These exhaust emissions pose serious
environmental and health risks. No maintenance or service
is required for the DOC device used on this generator.
Diesel Oxidation Catalyst (DOC)
The DOC (Figure 84) does not filter particles, it oxidizes
them. This catalyst (honeycomb-like structure) uses a
chemical process to break down pollutants in the exhaust
stream into less harmful components. In general this
catalyst collects/burns accumulated particulates. The DOC
contains palladium and platinum which serve as catalysts
to oxidize hydrocarbons and carbon monoxide.
DCA125SSIU4F 60 HZ GENERATOR • OPERATION MANUAL — REV. #6 (05/12/22) — PAGE 57
Figure 84. Diesel Oxidation Catalyst (DOC)
EMISSION CARBON CHECK
Deposition of carbon (soot, unburned fuel) in the exhaust
pipe line and muffler could cause not only system derates
but also could lead to fires.
To reduce soot and unburned fuel, run the unit at rated
power until the exhaust gas becomes mostly colorless every
250 hours of operation time. More carbon will be generated
when the unit operates at less then 30% of rated power. In
this case, perform the above procedures more frequently.
NOTICE
Applying a large load suddenly to the unit when
carbon deposition has been generated in the exhaust
system could produce sparks and will lead to abnormal
combustion. Therefore, apply load gradually and
observe the exhaust gas color during the process.
MAINTENANCE