Example: Applying A Protective Layer - Siemens SIMATIC ET 200S Operating Instructions Manual

5.7.5

Example: Applying a Protective Layer

Description
Metal parts are to be covered with a wax layer. The conveyor belt moves at a constant
speed. As soon as a metal part passes the initiator, the valve is opened. The distance the
item and the wax have to cover is proportional to the time.
The 2PULSE receives a 24 V enable signal from the initiator. The 2PULSE then generates a
24 V control signal at its digital output that opens the valve. The valve remains open while
the Initiator sends the 24 V enable signal to the 2PULSE.
To ensure that the wax hits the metal at the optimum time, a corresponding on/off-delay is
required.
Figure 5-30
Requirements
● The item is moved at a constant and quantifiable speed. (The distance is proportional to
● The valve only has the two positions OPEN and CLOSED.
● The minimum pulse duration must be longer than the on/off times specified by the
Technological Functions
Operating Instructions, 06/2010, A5E00124867-07
Applying a protective layer
the time.)
manufacturer.
2PULSE
5.7 Application Examples
337