Siemens sitrans, Инструкция по эксплуатации

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Page 10 SITRANS AS 100 – INSTRUCTION MANUAL 7ML19985DM02
This table provides a guideline for suitable wire gauges where distances are
considerable.
Maximum distance between Sensor and supply (24V or Control Unit)
*
nominal wire size
Analog Output
The Sensor provides an analog output proportional to the level of acoustic emission
activity. As the level of acoustic emission activity is a relatively good indication of process
or mechanical activity, the output is suitable as an input to devices such as dataloggers
chart recorders and programmable logic controllers.
The output is 0.08 to 10V (nominal), dc coupled, short circuit protected with a 60 µ s time
constant. The minimum load impedance is 100 K Ω . Refer to Installation on page 6 or
Interconnection on page 9.
Relative Sensitivity
The sensitivity of acoustic emission is affected by temperature. In most applications this
is not a concern when considering the much greater changes in signal level due to
changes in flow. However, it is important to be aware of the effect.
The sensitivity of the SITRANS AS 100 Sensor decreases with increasing temperatures at
a rate of approximately 0.5% per degree Celsius.
For example, if the temperature of the standard Sensor increased from 20 °C to 50 °C, its
sensitivity would decrease by 15%. If the Sensor were to be used to monitor flow
changes over such a temperature range, you should set an associated alarm setpoint at
least 30% away from the normal operating level measured at 20 °C.
wire size distance
AWG mm
mm
2
*
meters feet
24 7 x 0.20 0.22 500 1600
22 7 x 0.25 0.35 800 2600
20 10 x 0.25 0.5 1200 3900