Description

Proportional-pressure regulator VPPM

Characteristics At a glance
Innovative:
• Multi-sensor control (cascade control)
• Diagnostics
• Choice of control characteristics
• Temperature-compensated
• High dynamic response
• High repetition accuracy
• Modular system processing
• IO-Link® for direct connection to a higher-order IO-Link®/I-Port master
Flexible:
• Individual valves (inline valve)
• Sub-base valves (manifold/flanged valve)
• Various user interfaces: LED displays, LCD display, setting/selection buttons
• Choice of valves with different pressure ranges
• Pressure range can be modified at the valve
• Choice of different setpoint specifications: current input; voltage input
Operationally safe:
• Integrated pressure sensor with separate output
• Cable break monitoring
• Pressure is maintained if the controller fails
Easy to assemble:
• Manifold block (manifold)
• H-rail mounting
• Individually with mounting bracket
• QS fittings
Layout of a control loop (layout):
• The reference variable w (setpoint value e.g. 5 volts or 8 milliamperes) first acts on a comparator. The measuring equipment sends the value of the controlled varia-
ble x (actual value e.g. 3 bar) to the comparator as feedback variable r. The control element detects the control difference e and controls the final control element. The
output of the final control element acts on the system. The control element thus attempts to compensate for the difference between the reference variable w and the
controlled variable x by using the final control element.
Operating principle:
• This process runs continuously so changes in the reference variable are always detected. However, a system deviation will also occur if the reference variable is con-
stant and the controlled variable changes. This happens when there is a change in the flow rate through the valve, caused by a switching operation, a cylinder move-
ment or a load change. The disturbance variable z also causes a control difference, such as, for example, a pressure drop in the air supply. The disturbance variable z
has an unintended effect on the controlled variable x. The controller always tries to re-adjust the controlled variable x to the reference variable w.
Multi-sensor control (cascade control) of the VPPM:
• Unlike conventional direct-acting control systems, in multi-sensor control several control loops are nested inside one another. The overall controlled system is thus
divided into smaller sections that are easier to control for specific tasks.