SICK T-EASIC FTS, Operating Instructions Manual

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O P E R A T I N G I N S T R U C T I O N S | T - E A S I C
®
8023072/1E22/2022-02-23| SICK AG
Subject to change without notice
4 3
7 COMMISSIONING
For applications with water , an empty detection factor in the range of 90-140% is
useful. For oils and oil-like media , the empty detection factor should be between
70-90% to ensure reliable detection.
Empty detection factor
Empty Detect Factor
140%
100%
90%
70%
Response time
1)
Factory setting for water
Min water and max oil
Fast:
approx. 2-5 seconds
Slow:
approx. 10-25 seconds
Water
Oil
1)
For reference conditions: Pipe inner diameter 25 mm, water, vertical installation in the pipe, tip in the
middle of the pipe, probe oriented in the pipe as described in section 5.2 “Probe alignment to flow direction” ,
completely filled pipe without air bubbles, velocity between 10 cm/s and 100 cm/s, inlet zone > 30 cm,
outlet zone > 30 cm, 26 °C ± 1 °C, 2 bar ± 1 bar
Fig. 32: Configuring the empty detect factor
7.4.9 Low Flow Cutoff & Cutoff Hysteresis
Even when the valve is closed, convection or vibration of the pipeline can result in very
low flow rates. If the flow rate of a medium is zero, this can result in inaccurate measure -
ments. To ensure these measurements do not lead to undesired switching behaviors or
a wrong meter reading, the Low flow cutoff option can be used.
When enabled, flows that are within a narrow range around zero are treated by the
sensor as if the flow were at zero.
When the flow falls below a specified
“cutoff” value , the display and output are set to
zero (switch-on point). When the flow exceeds the set “Hysteresis” value again,
the measurements are continued (switch-off point).
If a value greater than 0 is entered as the “Cutoff” value, low flow cutoff becomes
active. In the factory setting, low flow cutoff is deactivated (“Cutoff” value = 0).
The switch-off point is specified as a positive hysteresis value as a percentage of the
switch-on point of the selected low flow rate. You can select values between 5% and
300% for the hysteresis. The factory setting is 50%.