Burkert 8681 - Pneumatic Interfaces; Magnetic and Mechanical Manual Override; Position Measuring System

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System Description
5.3.4 Pneumatic interfaces
•Intake & exhaust air connections (1/P,3/R): G 1/4
Working connections (2/A1...A3): G 1/8
•Integrated non-return valves in the solenoid valves' exhaust air duct
•
ActuationofConnection2/A1(SolenoidValve1;normallythemainstrokeoftheprocessvalve)usingthe
magnetic manual override that is externally accessible via magnetic manual override tool.
(bothsolenoidvalvesareactuatedsimultaneouslyvia magnetic manual override tool for the design for
double-actingactuators)
•Specialsilencerswithahighow-ratecapacitytoconnection3/Rhavealreadybeenmounted.
•The interior of the housing is protected against excessive overpressure, for example due to leakages, by a
pressure-relief valve with output into the joint exhaust air connection 3/R.
5.3.5 Magnetic and mechanical manual override
The control head provides the following as standard:
•Magnetic manual override for solenoid valve V1 (via magnetic manual override tool)::
easilyaccessiblefromtheoutside,onthebasisofencodedmagneticeldsforSolenoidValveV1(Con-
nection2/A1)aswellas
•Mechanical manual override:
oneachequippedsolenoidvalve,accessiblewhenthehoodisopen(see“Fig.6”onpage26)
The magnetic manual override (for 2/A1 or V1) has the following advantages:
•the control head does not need to be opened
•
simpleactuationtoolforopening/closingsolenoidvalveV1(mainstroke)-
helpful for service/maintenance work on the process valve (V2andV3areswitchedoatthesametime;
both solenoid valves are actuated simultaneously with the magnetic manual override tool for the design
fordouble-actingactuators)
•LEDdisplayforthe"activated(magnetic)manualoverride"status=servicemode
(seechapters“21LEDColourAssignments” and “22ServiceMode/Manualoverride”)
Magnetic manual override is only applicable in automatic mode; in manual mode, V1 cannot be
switched using the magnetic manual override tool.
For a detailed description of the manual override, see chapter
“22ServiceMode/Manualoverride”.
5.3.6 Position measuring system
The switching positions of the process valves are reported to the actuator by feedback signals from the
inductive position measuring system.
The connection to the control head is done by means of a simple adaptation to the process valve's piston
(valvespindle).Detailsaredescribedinchapters“6.7Positionmeasuringsystemdata”onpage27 and
“20PositionMeasuringSystem”onpage129.
english
Control Head Type 8681