Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 139)

IM 11M13A01-04E 10-21
10. Other Functions
(2) Next, adjust the flow rate to 600
Ϯ 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
Ϯ 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.
<Treatment after completion of calibration>
(1) Fully close the needle valve mounted on the calibration gas inlet of the detector.
(2) Remove the tube connecting the detector to the standard gas unit.
WARNING
Store the standard gas unit with the gas cylinder mounted where the ambient temperature
does not exceed 40˚C. Otherwise, the gas cylinder may explode. Store the spare gas
cylinders under the same condition.