Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 148)

IM 11M12A01-05E 10-21
10. Other Functions
<Flow of span gas (air)>
The standard gas unit is used only when manual calibration is employed.
Therefore, the timing for flowing span gas (air) is included in the manual calibration
flowchart described in Section 7.10.2, earlier in this manual. For operation of the
converter, see Section 7.10.2.
(1) When the “OPEN” and “the measured oxygen concentration” are alternately dis-
played during calibration, plug the power cord into the power supply socket to start
the pump of the standard gas unit.
(2) Next, adjust the flow rate to 600 6 60 ml/min using the span gas valve “AIR” (the
flow check ball stops floating on the green line when the valve is slowly opened). To
rotate the valve shaft, loosen the lock nut and turn it using a flat-blade screwdriver.
Turning the valve shaft counterclockwise increases the flow rate.
(3) After adjusting the flow rate, tighten the valve lock nut.
(4) After the measured oxygen concentration is stabilized, touch the [ENT] key, then all
the digits flash. Touch the [ENT] key again to display “ZERO Y” Disconnect the
power cord to stop the pump.
<Flow of zero gas>
Touch the [ENT] key to display a zero-gas value set with the parameter code B01.
Touch the [ENT] key again to flash “OPEN” and the “measured oxygen concentration”
alternately. To cause the zero gas flow, follow these steps:
(1) Use the needle of the zero gas valve “CHECK GAS” to puncture a hole in the gas
cylinder installed as described in Section 10.5.2. Fully clockwise turn the valve
regulator by hand.
(2) Next, adjust the flow rate to 600 6 60 ml/min (the flow check ball stops floating on
the green line when the valve is slowly opened). Turn the regulator of the zero-gas
valve back slowly counterclockwise. At that time, the flow rate also decreases as the
inner pressure of the gas cylinder decreases. Monitor the flow check and, when the
ball’s position changes greatly, readjust the valve.
(3) Touch the [ENT] key after the measured oxygen concentration becomes stable.
Then all the digits flash. Touch the [ENT] key again so that the “CALEND” flashes.
Note
Be sure not to terminate the calibration in progress because of a shortage of gas in the
cylinder. Each gas cylinder is operable for nine minutes or more provided the gas is
discharged at the specified rate.
Therefore, if your calibration time is estimated at four minutes, you can operate the
zero-point calibration twice.
(4) Stop the zero-gas flow. Turn the zero-gas valve regulator fully clockwise. If this
valve regulator is not properly adjusted, the needle valve will not close completely
and a cylinder gas may leak. When the output stabilization time elapses, the calibra-
tion is complete.