Piping For The Detector With Pressure Compensation - YOKOGAWA EXAxtZR Instruction Manual

4.4 Piping for the Detector with Pressure Compensation

*1
4-12
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 style detector whenever the furnace pressure exceeds 5 kPa (see
Note). Even if the furnace 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.
The detector with pressure compensation is illustrated in Figure 4.13.
Note
Process gas pressure should not vary rapidly and widely.
Reference air outlet
Flange
*1 Dimensions may vary depending on the detector type. Refer to Section 3.8
Ensure that the flange gasket does not block the reference air outlet.
Where necessary, make a notch on the flange
Figure 4.13 Detector with Pressure Compensation
Ensure that process gas does not flow into the probe.
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.
156 3 69
Rc1/4 or 1/4NPT
PIPING
:B
(Calibration gas inlet)
*1
Stop valve
PIPING:A
Rc1/4 or 1/4NPT
(Reference air inlet)
2-G1/2, 2-1/2NPT or the like
(Wiring connection)
*1
*1
IM 11M12A01-02E
*1
C
Flange
F4.12E.EPS