KROHNE OPTISENS OAS 2000 EN - Manual (Page 17)

INSTALLATION
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OPTISENS OAS 2000
www.krohne.com 07/2010 - MA OAS 2000 R02 en
3.4 Mounting of submersible version
The sensor can be mounted in two ways:
• On a telescopic fibreglass rod placed in a mounting bracket that fastens to a handrail (see
next section).
• To an adjustable slide rail holder (see next section but one).
Installation tips
• When the sensor measures in a flume, it is important to find a place where the suspended
solids concentration is representative.
• Make sure the flushing nozzle is downstream from the lenses pointing against the stream.
This will avoid disturbances of the measurement by turbulence from the nozzle. At the same
time it will produce a shield around the nozzle, due to a constant over pressure, preventing
particles from getting in.
• Adjust the rod so that the sensor is at least 30 cm / 11.8" below the liquid surface or the
lowest water level in decant applications to prevent the sensor from coming out of the liquid.
• In an aeration tank, ensure that the sensor is not directly above a diffuser head. It should be
installed on the backside of the rolling diffuser effect.
• Flushing may not be required if the tank is well agitated. To verify the need for flushing,
remove the sensor from the liquid after it has been in the liquid for several days.
• When installing in a clarifier, compressed air flushing is required due to no agitation of liquid
and to remove oil and grease film on lens. This is especially applicable in primary clarifiers.
• When using the sensor for influent applications, always install the unit after the bar screen. If
the bar screen spacing is larger than 6 mm / 0.24", then a baffle or diffuser plate should be
installed in front of the sensor to prevent rags from catching on the sensor head. On influent
applications, compressed air flushing is recommended due to the oil or grease in the liquid.
3.4.1 Mounting to MAA 2000 telescopic rod immersion holder
The mounting bracket of the telescopic rod is mounted to a handrail or a separate holder.
In case a handrail is not available, a mounting post with a vertical bar for sensor mounting can be
purchased from the manufacturer.
.book Page 17 Friday, July 2, 2010 1:49 PM