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KROHNE BM 70 M User Manual

Page 48

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48

BM 70 M

Fct. 3.2.5 ERROR MSG.

Use this function to select whether errors are to be displayed during measurement.

NO: Error messages shown only in the error list, see Sect. 8.8

YES: When errors occur during measurement, display of the measured value will alternate
with error messages.

8.6.8 Current output I

Fct. 3.3.1. FUNCTION I

Use this function to select the measured variable.

OFF (= deactivated, the output supplies a constant 4 mA, e.g. necessary for HART

®

Multidrop;

Fct. 3.3.2 to 3.3.4 cannot then be selected, i.e. they are skipped over).

LEVEL

DISTANCE

CONVERSION

REFLECTION

SW.OUTP. (function and switching threshold are set in Fct. 3.6).

Fct. 3.3.2 RANGE I

Use this function to define the current in error condition. E = Error at 2 mA or 22 mA.

4-20 mA (hold last measured value when error occurs)

4-20 mA/E=2 (min. 3.6 mA for Ex-i output!)

4-20 mA/E=22

Fct. 3.3.3 SCALE 4 mA

This function does not appear (is skipped over) when "OFF" is set under Fct. 3.3.1.

This function is used for I min = 4 mA to define the lower value for level, distance, conversion
or reflection (scaling 4 mA).

Setting LEVEL or DISTANCE under Fct. 3.3.1:
Setting range and unit for SCALE 4 mA same as for Fct. 3.1.1 TANKHEIGHT. If a reference or
tank bottom offset is set, this must be allowed for!

Setting CONVERSION under Fct. 3.3.1:
Unit for SCALE 4 mA same as in Fct. 3.2.3 UNIT.CONV. But value must be smaller than the
maximum value in the conversion table.

Setting REFLECTION under Fct. 3.3.1:
The setting range for SCALE 4 mA is 0...99.

Fct. 3.3.4 SCALE 20 mA

This function does not appear (is skipped over) when "OFF" is set under Fct. 3.3.1.

This function is used for I max = 20 mA to define the upper value for level, distance,
conversion or reflection (scaling 20 mA)

Setting LEVEL or DISTANCE under Fct. 3.3.1:
Setting range and unit for SCALE 20 mA as for Fct. 3.3.1 TANKHEIGHT. The value set here
should not be greater than the response threshold. (Response threshold = tank height
(Fct. 3.1.1) - block distance (Fct. 3.1.2)). If a reference or a tank bottom offset is set, this must
be allowed for!

Setting CONVERSION under Fct. 3.3.1:
Unit for SCALE 20 mA same as in Fct. 3.2.3 UNIT.CONV. The value set here must be greater
than that of Fct. 3.3.3, otherwise error during Parameter Check.

Setting REFLECTION under Fct. 3.3.1:
The setting range for I max = 20 mA is 1...100.
The value set here must be greater than that of Fct. 3.3.3, otherwise error during Parameter
Check.