Samson 3766 - Adjusting the Position Transmitter

44 EB 8355-1 EN
Operation
5.4 Adjusting the position
transmitter
The starting point (zero) and upper range
value (span) must be set before adjusting the
position transmitter.
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.
Fig.14: Position transmitter
Zero point
Use the switches 1 and 2 to roughly set the
zero point and the ZERO potentiometer for
ne-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ne-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10.
NOTICE
!
Table10: 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 connector'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 connector's position
20mA ValveOPEN
4mA ValveCLOSED