Recommendation For Selecting Parameters; Preparation; Damping Using Parameters P.41, P.42, P.43 And; Main Alarm Threshold Via Parameters P.6, P.8, P.10 And - Siemens SITRANS DA400 Operating Instructions Manual

Commissioning

8.2 Recommendation for selecting parameters

8.2 Recommendation for selecting parameters
8.2.1

Preparation

Note
After turning on the power supply, the device performs a self-test "SELF Test". After
completion of the self-test, approximately 5 seconds, the device is ready to use. Acoustic
channel 1 "1/SO1" is shown in the digital display.
Procedure
1. Turn on the power supply on the device.
2. Be certain that there is sufficient material flowing in the pipe or duct to specify the limit.
3. For each measurement channel used, set the parameters P.1 to P.4 associated with the
measurement channel to the value "on L" or "on H". Leave measurement channels not
used on "oFF".
4. For each measurement channel used, set the parameters P.41 to P.44 associated with
the measurement channel to the value "0 s".
5. Observe the measured value for each acoustic channel for about one minute. The
subsequent procedure depends on the measured values read here. These are described
in the following sections.
8.2.2 Damping using parameters P.41, P.42, P.43 and P.44
These parameters are used to optimally adjust the response time of the diagnostics unit. The
greater the set parameter value is, the less the effect of brief fluctuations on the measured
value.
Increase the parameter associated with the measured value until the fluctuations of the
measured value are less than ±3 dB under normal operating conditions.
8.2.3 Main alarm threshold via parameters P.6, P.8, P.10 and P.12
When the set value is exceeded (longer period of time than the response time P.13), the
main alarm signals that there is a sufficient mass flow or a permissible mass flow has been
exceeded.
Not every signal necessarily indicates permanent shortfall or exceedance.
Thus, set the value for the main alarm in such a way that small sound level increases will not
produce a signal. In this case, use a pre-alarm if necessary. Set the limit value for the main
alarm at a value which is around 3 dB over the largest of the measured values read off.
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SITRANS DA400 for material flow monitoring with protection against explosion
Operating Instructions, 09/2007, A5E00841152-01