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ecom-CN
They will be stored there for a later printout and, if need be, a final
data record storage (you can view the values in the intermediate
memory by pressing
<F4>
- during the inquiry the gas pump switch-
es off).
The CO sensor is protected against overload by the internal pro-
gramme. If the limit value of 4000 ppm is exceeded, a second pump
switches on and flows the sensor with fresh air. The sensor with can
be switched into the measuring mode by pressing the
<F2>
key (the
sensor can also be switched off by pressing the
<F2>
key).
4.3. CO measurement (safety check)
The check of gas-fired plants for operation safety reasons is per-
formed with the CO measurement. The CO content in the exhaust
pipe is measured after the flow fuse and converted on an undiluted
value (residual oxygen value in exhaust gas = 0 %).
As the gas behaviour after the flow fuse is no more homogeneous
because of the flow in of secondary air and the core stream meas-
urement could consequently be erratic, the gas analysis is performed
over the total diameter of the pipe. A multi-hole probe serves as
sampling probe hereto (optional accessory).
The calculated value indicated on the line CO 0.0% corresponds to
the measured CO content supposing that the oxygen content would
amount 0% in the same gas volume. It is consequently the undiluted
CO content in exhaust gas. Once the value is stable, press
<record>
to store the value in the intermediate memory.
CO-measur.
O2
17.5 %
CO 0.0%
738 ppm
CO
123 ppm
Lambda
7.00
m
Measurement
stored in inter-
mediate memory
Summary of Contents for CN
Page 1: ...Operating Instructions ...
