Needle Stroke Monitoring; Light Barrier; Process Monitoring - Walter Valve Controller Originalbetriebsanleitung

7.4.6

Needle Stroke Monitoring

This monitoring checks whether the needle of the valve opens as required. If it does not open, there
is an error. If the number of errors in the entire parameter set is still within the tolerance, the error is
ignored. If the number is outside this, the user is shown not OK. The signals at the digital outputs are
OK/not OK (If the I/Os are configured accordingly) remain until the start of the next dosing procedure.
7.4.7

Light Barrier

The light barrier monitors whether the medium is coming out of the valve. Within an adjustable time
after the activation of the valve medium, the light barrier must break through. If the time until the light
barrier is broken is too long, the shot is regarded as faulty.
7.4.8

Process Monitoring

All three monitoring functions run for themselves and are evaluated at the end of a parameter set. In
each parameter set, a check is made as to whether the monitoring functions output OK. OK can only
be output if each monitoring is within the tolerance.
Example:
A shot sequence with 10 shots and a tolerance of 10% was defined.
Case 1:
The needle stroke monitor correctly detects 9 shots, the pressure monitor correctly detects 10 shots.
The process monitoring evaluates the process as correct and outputs an OK signal.
Case 2:
The needle stroke monitor correctly detects 9 shots, the pressure monitor correctly detects 8 shots.
The process monitoring evaluates the process as faulty and gives an n.OK Signal off.
WVC
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