Burkert 323219, Быстрый старт

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Technical data
Internal position sensor
Axle for position sensor
Cable gland
Electronic module
Pilot valve system
Fig. 2: Structure, positioner Type 8791
5.2 General description
The positioner Type 8791 is a digital, electro-pneumatic position
controller for pneumatically actuated continuous valves. The device
incorporates the main function groups
- Position sensor
- Electro-pneumatic pilot valve system
- Microprocessor electronics
The position sensor measures the current positions of the con-
tinuous valve. The microprocessor electronics continuously
compare the current position (actual value) with a set-point
position value specified via the standard signal input and sup-
plies the result to the position controller. If there is a control
difference, the electro-pneumatic valve pilot system corrects the
actual position accordingly.
6 TECHNICAL DATA
6.1 Standards and directives
The device complies with the relevant EU harmonisation legis-
lation. In addition, the device also complies with the require-
ments of the laws of the United Kingdom.
The harmonised standards that have been applied for the con-
formity assessment procedure are listed in the current version of
the EU Declaration of Conformity/UK Declaration of Conformity.
6.2 Operating conditions
WARNING!
Solar radiation and temperature fluctuations may cause mal -
functions or leaks.
▶
If the device is used outdoors, do not expose it unprotected
to the weather conditions.
▶
Ensure that the permitted ambient temperature does not exceed
the maximum value or drop below the minimum value.
Ambient temperature See type label
Degree of protection IP65 / IP67
1)
according to EN 60529
(only if cables, plugs and sockets have
been connected correctly)
Operating altitude up to 2000 m above sea level
1) If the positioner is used under IP67 conditions, the ventilation filter
(see “Fig. 1”) must be removed and the exhaust air conducted into the
dry area.
Type 8791 REV.2
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