Hanna Instruments HI520 - General Installation Considerations; Installation Schemes & Mounting

149 Measuring with Optical Dissolved Oxygen (DO) Probes
24.2. GENERAL INSTALLATION CONSIDERATIONS
• Probes are easily installed using the ¾” NPT external threads.
•
Hand tighten the probe in position. Then, depending on the process, tighten one or two turns with a wrench
to secure in place. Do not exceed the 10 N•m (7.3 lb‑ft) torque specification for the probe sensor.
• Protect the probe and the Smart Cap from strong flow to prevent unstable readings. In turbulent aeration
basin installations, place the probe in a weir for more accurate readings.
• Position the probe so that it does not trap air bubbles at the Smart Cap.
• Deposits of foreign material should not be allowed to accumulate within the sensing area.
• Protect the sensing surface from blunt objects and is keep it clean.
• Provisions must be made for the removal of the probe from the process.
• Consider probe accessibility for maintenance when selecting placement.
Note: See Optical DO industrial probes manual (MAN7640-58) for series configuration options and detailed
specifications.
24.3. INSTALLATION SCHEMES & MOUNTING ACCESSORIES
Accessories are sold separately!
24.3.1. Probe Dimensions
3/4’’ NPT
Ø 17 mm (0.7”)
Ø 28 mm (1.1”)
3/4’’ NPT
172 mm (6.7”)
64 mm (2.5”)
43 mm (1.7”)
Figure 71: HI7640‑58ZZ optical DO with attached cable
172 mm (6.7”)
Figure 72: HI7640‑5800 optical DO with DIN connector
24.3.2. Probe Connection
Align the pins and key then push the plug into the socket.
Rotate the collar to lock in place.
Note: Probe connection (probe with integral DIN connector) and probe wiring (probe with attached cable)
must be carried out with the controller disconnected from power.