Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 70)

<4. Pipomg>
4-10
IM 11M12A01-02E 8th Edition : Jan.13,2012-00
4.4 Piping for the Detector with Pressure
Compensation
The ZR22G----P Detector with Pressure Compensation may be used in System 2 and
System 3. However, it cannot use piping for high temperature probe adapter or blow back piping.
Use this detector whenever the furnace pressure exceeds 5 kPa (see Note). Even if the furnace
pressure is high, the detector can measure by adjusting pressure of the detector to the furnace
pressure using instrument air. The inside pressure of the probe will be kept the same as the
furnace pressure by feeding instrument air at higher pressure than that in the furnace.
NOTE
Sample gas pressure should not vary rapidly and widely.
*1
*1
*1
*1
Flange
156 87
Rc1/4 or 1/4NPT
Calibration gas inlet
25 48
Reference gas outlet
Flange
PIPING
PIPING
Stop Valve
Rc1/4 or 1/4NPT
Reference gas inlet
2-G1/2, 2-1/2NPT etc.
Cable connection port
*1 Dimensions may vary depending on the detector type. Refer to Section 2.2
Ensure that the flange gasket does not block the reference gas outlet.
Where necessary, make a notch on the flange
F4-12E.ai
*1
Figure 4.13 Detector with Pressure Compensation
Valve operation
1. For safety, stop the furnace that the detector is to be installed in. If furnace internal pressure
is high, this is especially dangerous.
2. Before starting instrument air flow, completely shut the stop valve in front of the reference
gas outlet.
3. Check that the reference gas outlet is not blocked by a flange gasket or the like.
4. Set the instrument air pressure higher than furnace internal pressure.
5. Completely open the stop valve in front of the reference gas outlet and, after turning on
instrument air flow, start furnace operation. As furnace internal pressure rises, confirm
that instrument air continues to flow and adjust the valve or increase supply pressure if
necessary.
6. After furnace internal pressure stabilizes, adjust flow.
7. If furnace operation is stopped, stop instrument air flow and completely shut the stop valve
in front of the reference gas outlet. You may leave reference gas flowing if you wish.