Hach ORBISPHERE K-M1100 Basic User Manual page 13

4.8 Sensor installation
4.8.1 Sensor positioning
The sensor must be installed in a socket or flow chamber that allows contact with the sample fluid to
be analyzed. The sensor and measuring instrument are connected by a cable. The standard sensor
cable lengths are 3, 5, 10, 15 and 20 meters. Ensure that the sensor will be mounted:
• perpendicular to the pipe
• on a horizontal pipe section (or on flow-ascending vertical pipe)
• minimum of 15 meters away from the pump's discharge side
• in a place where the sample flow is stable and rapid, and as far as possible from:
• valves
• pipe bends
• the suction side of any pumps
• a CO injection system or similar
2
Note: There may be situations where not all the above conditions can be met. If this is the case, or you have any
concerns, please consult your Hach representative to appraise the situation and define the best applicable solution.
4.8.2 Recommended sample flow rate
For optimal response time, the recommended sample flow rate for both the K1100 and
M1100 sensors is 150 mL/min. Control the flow with the outlet valve on the flow meter (No. 3 in
Figure 8) to avoid foam developing inside the flow chamber which could lead to erroneous oxygen
measurement values.
Figure 8 Typical measurement schematic
1 Valve to redirect sample for measurement
2 Sensor and flow chamber combination
Section 5 User interface
5.1 Instrument controls
The instrument front panel provides:
• A touch screen acting as display, touch pad and keyboard.
• A LED, showing when the instrument is on.
Turning instrument On and Off
There is no power switch on the instrument. The mains must be disconnected to turn the instrument
off.
Measurement window
The main (numeric) measurement window continuously displays:
3 Flow meter with outlet valve
4 Drain
English 13