YOKOGAWA PH8EFP, Руководство пользователя

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IM 12B7J1-01E
< 2. Installation >
2-9
(3) If specified, a reserve tank containing 250 mL solution and mounting hardware to hold this
tank, or a medium pressure reserve tank are supplied with the PH8EFP pH sensor.
Attach the mounting hardware for general purpose reserve tank to a pipe (2-inch). Connect
the general purpose reserve tank to the KCl solution supply tube of the sensor. Remove the
cap from the tank and screw the tube connector securely into the tank.
When using a medium pressure reserve tank, attach it to a pipe (2-inch) and perform air
piping to supply pressure for reserve tank as shown in Figure 2.11. Connect the KCl supply
tube of the sensor to this reserve tank.
Air Pressure
Regulator
Air Supply
Pressure Gauge
To pH Sensor
Maximum Measured Solution
Pr10 kPa
Figure 2.11 Air Piping for Pressurizing Medium Pressure Reserve Tank
(4) Supply KCl solution to the sensor.
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When a general purpose reserve tank is used.
First, mount the reserve tank on the holding hardware with the tube connection part directed
downwards. Using the pin supplied with the tank, make several holes in its top (see Figure 2.3).
Stand the sensor upside down at a position lower than the reserve tank as shown in Figure 2.3
so that KCl solution flows from the tank into the sensor. When the KCl solution fills the sensor
and overflows from the liquid junction mounting hole, securely screw the liquid junction into the
mounting hole.
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When a reserve tank for medium pressure is used.
First, fill the reserve tank with KCl solution (*1). Loosen the nut on the reserve tank upside and
remove the cap — the pressure gauge is mounted — and pour about 250 mL or KCl solution into
the tank. Stand the sensor upside down at a position lower than the reserve tank so that solution
flows from the tank into the sensor. When the KCl solution fills the sensor and overflows from the
liquid junction mounting hole, securely screw the liquid junction into the mounting hole. Remount
the cap of the reserve tank. Tighten the nut securely.
*1: Use 3.3 mol/L KCl solution. If KCl powder (ordered separately) are supplied with the PH8AX accessories, dissolve one bag (60 g)
of KCl powder in pure water to make exactly 250 mL of solution.
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When a Big-volume reserve tank is used.
Fill the reserve tank with a KCl solution. Loosen and remove the top cover on the reserve tank
and pour a KCl solution of approximately 500 mL. When loosening or closing the cover, always
do so while holding the reserve tank by hand. When further tightening the fixing nut at the bottom
of the reserve tank, be careful not to tighten it too tight.
Excessive tightening may cause cracks in the reserve tank and thus leakage of KCl solutions.
This will make grounding connections at two points, resulting in unstable readings or
measurement errors.
12th Edition : Dec.14,2018-00