Burkert Type 8793 - Manual (Page 13)

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Description of System
6. DESCRIPTION AND FEATURES OF THE
TYPE 8792/8793
6.1. General description
The positioner Type 8792 / process controller Type 8793 is a digital, electro-pneumatic position controller for
pneumatically actuated continuous valves. The device incorporates the main function groups
- Position sensor
- Electro-pneumatic control system
- Microprocessor electronics
The position sensor measures the current positions of the continuous valve.
The microprocessor electronics continuously compare the current position (actual value) with a set-point position
value specified via the standard signal input and supplies the result to the positioner/process controller.
If there is a control difference, the electro-pneumatic control system corrects the actual position accordingly.
6.1.1. Features
• Models
- Positioner (position controller) Type 8792
- Process controller with integrated position controller, Type 8793.
• Position.sensors.
- internal high resolution conductive plastic potentiometer or
- external non-contact, non-wearing position sensor (remote).
• Microprocessor-controlled.electronics
for signal processing, control and valve control.
• Operating.module.
Operation of the device is controlled by four keys. The 128 x 64 dot matrix graphics display enables you to
display the set-point or actual value and to configure and parameterize via menu functions.
• Control.system.
The control system consists of 2 solenoid valves and 4 diaphragm reinforcers. In single-acting actuators the
working connection 2 must be sealed with a threaded plug.
• Feedback.(optional).
The feedback is implemented either via 2 proximity switches (initiators), via binary outputs or via an output
(4 – 20 mA / 0 – 10 V).
When the valve reaches an upper or lower position, this position can be relayed e.g. to a PLC via binary outputs.
The operator can change the initiators or limit positions via control lugs.
• Pneumatic.interfaces.
Internal thread G1/4“
• Electrical.interfaces.
Circular plug-in connector or cable gland
• Housing.
Plastic-coated aluminium housing with hinged cover and captive screws.
English
Types 8792, 8793