Hach-Lange 1720E Low Range Turbidimeter - Manual (Page 18)

14
Installation
Figure 5 Sampling Techniques
3.5 Sample Connections
Sample inlet and drain connections are made on the turbidimeter body. The sample inlet
fitting installed in the body is a ¼-inch NPT
x ¼-inch compression fitting. One additional
fitting supplied with the instrument is a ½-inch NPT-to-hose fitting for use with ½-inch ID
flexible plastic tubing on the drain.
Note: For samples with high solids content (high turbidity), operate at the highest flow rate possible.
For samples with low solids content (low expected turbidity), operate at a low flow rate
(200–300 mL/min).
The required flow rate is 200 to 750 mL/min (4.0 to 11.9 gal/hour). Flow rate into the
turbidimeter may be controlled with a flow restriction device on the inlet line. Flow rates
below 200 mL/min will reduce response time and cause inaccurate readings. Flow rates
above 750 mL/min will cause the turbidimeter to overflow, indicating flow rate is too high.
Figure 6 Sample Connections
1. Sample Flow 4. Sediment (Typical) 7. Good
2. Sampling Line to Sensor 5. Poor 8. Best
3. Air (Typical) 6. Poor
5 6 7 8
3
1
2
4
1. Sample Inlet, ¼-28 NPT x ¼-inch Compression fitting 2. Drain, ½-inch NPT fitting 3. Service Drain
POWER STATUS
1
2
3