Inspectors – get insights

1. Actual measured value graph
2. Reference graph
3. Tolerance band
4. Measurands violating thew tolerance band
5. upper tolerance deviation
6. upper tolerance deviation

1. Actual measured value graph
2. Reference graph
3. Tolerance band
4. Measurands violating thew tolerance band
5. upper tolerance deviation
6. upper tolerance deviation

Monitoring of parameters provides a real-time insight into the weld process. Current monitoring with the I-Inspector tells if for example the requested set value has been achieved or not. A bandwidth is set as tolerance in which the paremeter, here current, shall be. If one of the tolerances are violated a message is issued. This message number is shown on the HMI XPegasus, on the backlight display on Genius units (GeniusMFI, GeniusHWI and GeniusACs) as well on the fieldbus (if applicable).

A measurement frame can be set automatically or manually. The active measurement frame is shown as green area within XPegasus. Everything outside is shown as red where the inspector is blind or just ignores the values in other words. The red section at the begin of each process is called also blind time.

The tolerance band can be set absolute or envelope curve with a real reference recorded reference in the background. Monitoring does operate per schedule to cover different processes individually. In other words the user can attach different monitoring to the schedules for individual treatment.

Fig. 2-12 XPegasus display with opened I-Inspector settings

Voltage is the most senstitive parameter from the parameter set giving information where other parameters do not give enough. The inspector works exactly the same way as the current inspector (I-inepector) from the perspective of the settings. When you know one inspector from the settings, you know the other.

Reference curve, envelope monitoring or absolute as well as blind time setting and monitoring range are part of the inspector. When you refer back to the current inspector above you will see what changes for you is the unit current turns into voltage.

Fig. 2-13 XPegasus view with U-Inspector settings open

In the two sections above you learned about the current and voltage inspectors. Using Ohms law gives the resistance which is then displayed in the resistance inspector (R-Inspector). This ohms resistance is the sum of all resistances in the secondary loop of your welding system from the transformer through the welding gun arms or shanks of your machine, through the material. When resistance changes it may be caused by sealer between the sheet metals, oil, coatings, shunts and more.

This parameter does give you as user an insight how your system performs. Slowly raising resistance can be treated as slow wear of components; changes from part to part more on changes between the parts.

Also here settings are the same as on the other inspectotrs – keep it simple for you as user – but get a different message what the resistance does tell in the current weld process.

Fig. 2-14 XPegasus display with R-Inspector settings open

By using control methods, the actuating value (PWM pulse width) can be changed in such a way that the welding current or voltage remains constant regardless of disturbing influences. The change in the actuating value during a weld is an indicator of how great the influence of disturbance variables is. The H-lnspector compares the changes in the control value during welding with a reference curve and issues a warning if a preselected tolerance is exceeded or classifies the weld as faulty. The reference curve can be formed from the default values of the control system or from the measured values of a weld that has been classified as good. Permitted deviations from the reference curve of a weld are specified as envelope curves. These can have a constant or a proportional distance to the reference curve.

Fig. 2-15 XPegasus display with H-Inspector settings open

The Q-lnspector compares the dynamic resistance curve of a weld with a previously formed reference and evaluates the similarity. Special attention is paid here to the simplicity of operation. The reference is determined from tested welds and thus represents an optimized resistance curve. This reference is assigned a value of 1 (100%). Each subsequent weld is evaluated for similarity using an internal algorithm. This value is called “Spot Value” and can be used as a monitoring parameter with an individually adjustable threshold. References for different welding tasks can be stored in a database and reloaded as needed. As information, the current resistance curve is mapped in relation to the reference during production. In addition, the user receives an overview of the past evaluations in a live process drift display. The Q-lnspector is based on statistical data and should therefore only be used with XPegasus Gold or higher, as the extended database enables optimal quality control over longer periods of time.

Fig. 2-16 XPegasus surface Q-lnspector

The S-Inspector does take care about mechanical values of your weld process. A displacement transducer needs to be installed and be attached to your GeniusMFI, GeniusHWI or GeniusACs. The inspector does monitor the travel (sink-in) and also checks paralell the presence of the current item. In case a weld not for example is not in place, travel of the electrodes is overshooting. This generates a message. On the other hand, in case the sink-in for a weld is not achieved another message is issued.

Both ways, presence and travel during weld (sink-in) can me monitored or just one – its up to the user to make the selection.

Fig. 2-17 Component inspection, entry distance or gauge block monitoring