Samson 3767, Перевод оригинальной инструкции

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EB 8355-2 EN 5-25
Installation
5.6 Adjusting the optional
position transmitter
The starting point (zero) and upper range
value (span) must be set before adjusting the
position transmitter (see section 5.5.2).
Depending on the position of the multi-pin
connector (symbol on connector: >> or <>),
the feedback signal can be set to either a
range of 4 to 20 mA or 20 to 4 mA for 0 to
100 % travel.
ZERO
SPAN
12
34
SPAN
ZERO
Fig. 5-13: Position transmitter
Zero point
Use the switches 1 and 2 to roughly set the
zero point and the ZERO potentiometer for
fine-tuning. The adjusted value is always
based on a 4 mA signal.
Span
Use the switches 3 and 4 to roughly set the
span, i.e. the upper range value and the
SPAN potentiometer for fine-tuning. The ad -
justed value is always based on a 20 mA
signal.
Example:
Move the valve to the open position while
observing the position transmitter signal.
If the signal does not move in the desired di-
rection, change the position of the multi-pin
connector.
Adjust the zero point (4 mA) and span
(20 mA) for the valve positions according to
Table 5-4.
Table 5-4: Position transmitter
Valve movement Observed feedback signal Direction of signal Set zero/span to
Open
á
Closed
Signal increases
á
OK
20 mA Valve OPEN
4 mA Valve CLOSED
Not OK
à
Change connec-
tor's position
4 mA Valve OPEN
20 mA Valve CLOSED
Signal drops
â
OK
4 mA Valve OPEN
20 mA Valve CLOSED
Not OK
à
Change connec-
tor's position
20 mA Valve OPEN
4 mA Valve CLOSED