715 Portable – Instruction Manual
2 Operation
The 715 is ready for operation once the power switch is moved to the ON position. Before using
the 715 to determine the sludge interface position, it is worthwhile performing the operation test
below.
2.1 Operation Test
The operation of the 715 can be quickly checked. When the unit is switched on and the sensor
gap is clear (sensor in air or in clean water) the unit should emit a fast bleep and the LED should
not be illuminated. If the sensor gap is then blocked, the unit will switch to a slow bleep and the
LED will illuminate. Unblocking the sensor should return the unit to a fast bleep with the LED off.
2.2 Sludge Interface Detection
Release the sensor and allow it to hang below the cable reel. Slowly lower the sensor into the
settling tank, listening for a change in the sounder output. When the sound changes, the sludge
blanket has been detected, and the lowest visible cable marking indicates the position of the
sludge blanket below the supernatant surface.
2.3 Cleaning
After use the sensor should be cleaned by rinsing with clean water. On a regular basis the
sensor and sensor cable should be cleaned by rinsing with a solution of water and a mild
detergent. The cable reel can be cleaned using a damp cloth and mild detergent.
Note: The cable reel should not be immersed
2.4 Reeling Technique
When using the 715, the sensor cable should not be allowed to go slack when reeling the
sensor in or out. If the cable is allowed to become slack, it is possible for the cable to jam inside
the cable reel – if this does occur the cable must be carefully freed – the cable reel must not be
forced.
156770IM-Issue 07 Issue Date 24/10/2010
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