Detecting Wire Breaks; Split Range Control - Baelz Automatic 373-E66 Series Operating Instructions Manual

Operating Instructions

7.8 Detecting wire breaks

The wire break detection function permits detection of incorrect input signals. This function can be activated or de-
activated using switch S1.5. To use this function, the input signal must be set to 4...20 mA or 2...10 V. When using
the wire break detection function with the input signal set to 0...20 mA or 0...10 V, a malfunction of the positioner
will occur. The fail-safe function is triggered as soon as the input signal is below 3.5 mA.
Use switches S1.3 and S1.4 to set the actuator behaviour in case of a signal failure.
DIP switch positions
S1.1 S1.2 S1.3
X
X
S1.1 S1.2 S1.3
X
X
S1.1 S1.2 S1.3
X
X
Figure 19: Cable break detection

7.9 Split range control

To adjust split-range control, apply the set point for the upper end position (e.g. 12 mA) to the actuator. Turn po-
tentiometer P2 until the stroke corresponds to the upper end position. Turning the potentiometer counter-clockwise
causes the actuator spindle to retract.
The lowest value that can be set for the upper deactivation point is ~8 mA or ~4.0 V.
Then set the set point to the lower end position (e.g. 6 mA). Turning potentiometer P1 counter-clockwise causes
the actuator spindle to extend. The upper value that can be set for the lower deactivation point is ~13.2 mA or
~6.6 V.
Check the end positions by moving the valve to its upper and lower end position.
Technical specifications subject to change
W. Bälz & Sohn GmbH & Co.
Phone +49 (0)7131 15 00 0
S1.4 S1.5
X
X X
S1.4 S1.5
X X
X
S1.4 S1.5
X X
X
Koepffstrasse 5
Fax +49 (0)7131 15 00 21
Function
ON
Fail as is
OFF
ON
Fail open
OFF
ON
Fail close
OFF
BA 373-E66
Observe copyright protection DIN 34
74076 Heilbronn
www.baelz.de mail@baelz.de
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Germany