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<2. INSTALLATION, PIPING, AND WIRING>
2-16
IM 12B01B30-02EN 2nd Edition : June 09 , 2021-00
(2) Piping of the Sample Line from the Detector
This piping is for draining a sample form the measurement cell of the detector during
measurement. As shown in the piping diagram in Figure 2.24, connect a needle valve to the
sample outlet of the detector. By adjusting the opening of this valve and the bypass valve
(needle valve) at the top of the pressurized head tank, the pressure change is controlled in the
piping between the head tank and the detector outlet, and thus the generation of air bubbles is
prevented.
1. To the sample outlet of the detector, connect a fitting, such as an elbow fitting,
corresponding to the connection size (Rc1/2 or 1/2 NPT female) and a needle valve.
2. To the outlet of the needle valve, connect a 8 mm OD x 6 mm ID polyethylene tube using the
corresponding fitting to drain the sample to a drain pipe.
3. As shown in Figure 2.24, the sample from the detector should be discharged to the
atmosphere at a point higher than the measurement cell of the detector. If not, a siphon
may be created and the measurement cell may not be filled with a sample. In addition, if the
sample inflow stops, the sample will be drawn off and the measurement cell will be emptied,
which can cause damage to the ultrasonic transducer, if used.
(3) Drain Piping
This piping is for draining a sample from the measurement cell of the detector and a head tank
during cleaning, calibration, or other maintenance.
1. The drain of the detector is Rc1/2 (or 1/2 NPT female) thread. Install a fitting corresponding
to the thread and connect a hose/tube with sufficient diameter that provides adequate flow
of sample, to route the sample from the detector to a drain pipe. Install the pipe so that no
stagnation occurs.
2. As shown in Figure 2.24, install pipe so that the sample can be drained from the head tank
to the drain pipe.
(4) Piping of the Zero Water Line
This piping is for introducing tap water to a zero turbidity filter and then to the detector for zero
calibration or measurement cell cleaning.
1. As shown in Figure 2.24, install a tap water valve and a zero water drain valve.
2. Connect a zero water supply valve to one end of the 3-waytee fitting attached to the sample
inlet of the detector.
3. Install a fitting corresponding to the piping connection of the zero turbidity filter and connect
an hose/tube that can withstand the pressure of tap water, such as a rigid PVC tube. The
flow rate of zero water supply should be in the range of 1 to 3 L/min.
4. For the specifications of the zero turbidity filter, see “1.3 Specifications”
5. To prevent corrosion of water inside the zero turbidity filter, allow water to flow through
the filter and flow out from the zero water drain valve continuously at a flow rate of
approximately 10 mL/min.