YOKOGAWA ZR22S, Руководство пользователя

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<7. Startup>
7-6
Table 7.1 Display Items
Item Primary value Secondary and
tertiary values
Display
Oxygen concentration
 
Oxygen concentration during measurement
Air ratio

Current computed air ratio
Moisture quantity

Moisture quantity (%H
2
O) in the exhaust gas
Output 1 item
 
Oxygen concentration with the equipment set for oxygen
analyzer (See *1 below.)
Output 2 item
 
Oxygen concentration with the equipment set for oxygen
analyzer (See *1 below.)
Current output 1

Output current value from analog output 1
Current output 2

Output current value from analog output 2
*1: If an analog output damping constant is set, the oxygen concentration display then includes these settings.
About the Air ratio:
“Air ratio” is defined as the ratio of (the amount of air theoretically required to completely burn all
the fuel) to (the amount of air actually supplied).
For this equipment, the air ratio will be obtained in a simplified way by measuring the oxygen
concentration in the exhaust gas. The air ratio may be expressed mathematically by:
m = { 1 / ( 21- Oxygen concentration ) }

21
If you use the air ratio data for estimating the combustion efficiency, etc., check that no air is
leaking in beforehand and that the measured value has not been affected by any interference
gas (CH
4
, CO, H
2
, etc.).
About moisture quantity:
The moisture quantity in the exhaust gas is calculated based on the parameters of the fuel setting
(refer to Subsection 8.6.3, “Setting Fuels”, later in this manual). The moisture content may be
expressed mathematically by:
Moisture quantity = {(water vapor content per fuel unit quantity) + (water content in air)}/ total
amount of exhaust gas
= ( Gw + 1.61

Z

Ao

m ) / ( X + Ao

m )
where,
Gw = Water vapor content in exhaust gas, m 3 /kg (m 3 )
Z = Ambient absolute humidity, kg/kg
Ao = Ideal air amount, m
3
/kg (m
3
)
m = Air ratio
X = Fuel coefficient, Nm 3 /kg or m 3 /m 3
For details on each parameter, refer to Subsection 8.6.3, “Setting Fuels”.
7.10 Checking Current Loop
The set current can be output as an analog output.
(1) Press the [Setup] key on the Basic panel display to display the Execution/Setup display.
Then select the “Maintenance” in the Execution/Setup display.
(2) Select the “mA-output loop check” in the Maintenance panel display to display the “mA -
output loop check” display, enabling you to check the “mA-output 1” and the “mA-output 2”.
Select the desired output terminal for current-loop checking (see Figure 7.15).
IM 11M13A01-02E