Eclipse Combustion EGA4 Manuale Utente

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Instruction Manual MM850481 ed.01 
4.1.2 
Water trap & line filter 
The gas flows through an external combined water trap and line filter to avoid the presence of condensation and 
suspended solid particles in the analysis section of the instrument. A cylinder is positioned at 15 cm from the instrument 
gas inlet it is divided into two parts: the water trap and the line filter.  
 
The water trap works using the expansion principle: the gas flow decreases its speed inside the cylinder and it will cool; 
the humidity will condense and the solid particles fall down. The section of the water trap must be periodically drained off 
to avoid water from entering the analysis section. Pull the rubber plug and shake slowly the trap to drain the water. Push 
the rubber plug to close the trap hole. 
 
The line filter is positioned after the water trap and before the electrochemical cell. Its function is to stop the smallest 
solid particles before the analysis. Remember to change the filter every time it is dirty. 
 
 
 
Line filter  
cat. EE650074 
Rubber plug 
cat. EE650081 
 
 
 
WARNING 
 
T
HE WATER TRAP MUST BE KEPT IN VERTICAL POSITION DURING GAS SAMPLING
. A
N INCORRECT POSITIONING OF THE TRAP CAN 
ALLOW THE WATER TO ENTER INSIDE THE ANALIZER AND DAMAGE THE ELECTROCHEMICAL SENSORS
 
NEVER 
MAKE ANY ANALYSIS WITHOUT THE DRAINING RUBBER PLUG
THE MEASUREMENTS WILL BE INCORRECT
 
W
HEN YOU FINISH THE ANALYSIS
REMEMBER TO DRAIN THE WATER TRAP
. B
EFORE PUTING THE GAS PROBE IN THE CARRYING CASE
REMUVE THE CONDENSATE WATER FROM THE PROBE HOSE
 
T
HE LINE FILTER SHOULD BE REPLACED WHEN DIRTY
. N
EVER MAKE ANY ANALYSIS WITHOUT LINE FILTER AND
/
OR WATER TRAP
AS IT 
CAUSES AN IRREVERSIBLE DAMAGE TO THE ELECTROCHEMICAL SENSOR
4.1.3 Gas 
sensors 
The analyzer uses long life sensors for O
2
, CO (H
2
 compensated), NO, NO
2
 and SO
2
. The sensor do not need special 
maintenance but must be replaced after the expected lifetime. 
However a full maintenance and certification of the instrument is recommended at one year interval
The gas sensors are electrochemical cells composed by two electrodes (anode and cathode) and an electrolyte solution. 
The sampled gas goes trough a selective diffusion membrane. 
The oxidation process produces an output electrical signal proportional to the gas concentration. The signal is evaluated 
by the electronics, converted to digital, processed by the microprocessor, displayed and printed with a 0.1% volume 
resolution. 
The flue gas must not be at a pressure that could damage or destroy the sensor. Measurements are always carried out 
under "pressureless" conditions. The maximum permissible excess/reduced pressure is ±100 mbar. 
Each sensor has a different response time: 
O
2
  
= 20s to 90% of reading 
CO (H
comp.)  = 50s to 90% of reading 
CO  
= 50s to 90% of reading 
NO  
= 40s to 90% of reading 
NO
2
  
= 50s to 90% of reading 
SO
2
  
= 40s to 90% of reading 
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