More efficient diagnostics via IO-Link Safety

Due to intense com­pet­i­tive pres­sure, oper­a­tors of pro­duc­tion plants must con­sider the effi­ciency of their machinery. This applies all the more to com­plex sys­tems. Today’s machinery must be even more flex­ible to operate because assembly times are expected to be shorter, while the number of com­po­nents to be installed is con­stantly increasing. This calls for flex­i­bility in the way machinery inter­acts, which cur­rent tech­nolo­gies must sup­port. One aspect is par­tic­u­larly rel­e­vant here: con­necting the plant and machinery so as to guar­antee secure, seam­less con­nec­tivity throughout the entire pro­duc­tion system.

In this field, the IO-Link Safety com­mu­ni­ca­tion pro­tocol is well on the way to pro­viding smarter, faster and more cost-effec­tive con­nec­tivity options as a dig­ital trans­for­ma­tion solu­tion. This is because IO-Link Safety is a tech­nology that allows safety sen­sors and actu­a­tors to be inte­grated quickly and easily, par­tic­u­larly in com­plex plants such as exten­sive con­veyor sys­tems.

New standard for communication

Any man­u­fac­turer and system builder that develops and pro­duces large-scale con­veyor sys­tems knows how time-con­suming the wiring can be. Each sta­tion – whether it’s an emer­gency stop button, a push­button or a status indi­cator for example – usu­ally requires sep­a­rate wiring to con­trol cab­i­nets or decen­tralised mod­ules and the cor­re­sponding eval­u­a­tion by the con­troller (stan­dard or safety). That’s a level of com­plexity that not only slows the project down, but also increases costs, cre­ates more poten­tial error sources and makes main­te­nance more dif­fi­cult. This is often the case: “Wiring = time-con­suming + error-prone”. IO-Link Safety changes this equa­tion: with a single cable con­nec­tion capable of han­dling both com­mu­ni­ca­tion and safety, machine builders not only save time, but also gain valu­able space in the con­trol cab­inet. Instead of spending days laying cables, con­necting wires and con­fig­uring con­ven­tional emer­gency stop or push­button sta­tions, engi­neers can rely on a plug-and-play archi­tec­ture that offers reli­a­bility without com­plexity. That’s because IO-Link Safety can dras­ti­cally reduce the instal­la­tion time – and there­fore also the engi­neering effort.

Faster assembly for a faster flow of goods

As the name sug­gests, con­veyors are used to trans­port mate­rial. This means that man­u­fac­turers or system builders, as well as oper­a­tors of con­veyor sys­tems, are often under con­sid­er­able time pres­sure, because cus­tomers need their con­veyors to be up and run­ning quickly in order to main­tain their own pro­duc­tion logis­tics. IO-Link Safety meets these cus­tomer require­ments. The key­words are: plug-and-play wiring, and a range of up to 20 metres from the IO-Link Safety Master to the first sensor or con­trol unit in the field. If addi­tional con­trol units or safety switches are con­nected in series, for example, this range can be extended. Layout plan­ning is sim­pli­fied greatly, while the classic con­straints of hard-wired safety sys­tems are also lifted. In addi­tion, the IO-Link Safety Master can also be used in rugged envi­ron­ments thanks to IP67 and IP69K pro­tec­tion – in met­al­working for example, where dust or swarf are com­mon­place.

All the benefits at a glance:

Safe conveyors with IO-Link Safety

A lot of plant and machinery, including with con­veyors for example, also require safety switches or safety locking devices to pro­tect human and machine. IO-Link Safety means that the simple inte­gra­tion of such sen­sors in the field or on con­veyors is seam­less. The sen­sors con­nected via the IO-Link Safety con­trol unit PIT­gatebox offer even more advan­tages, how­ever, as does the safety locking device PSEN­m­lock from Pilz. Its opti­mi­sa­tion poten­tial: the safety con­troller dis­plays the status of the gate and pro­tec­tion devices cen­trally, i.e. “open” or “closed” – enabling a faster restart and opti­mised reac­tion times when it comes to main­te­nance. If PSEN­m­lock is used via the con­trol unit PIT­gatebox, it is pos­sible to imple­ment pre­dic­tive main­te­nance – by recording oper­ating times – and diag­nos­tics can be extended to include status mes­sages for the safety locking device. Finally, appli­ca­tions can be up and run­ning faster thanks to M12 plug-in con­nec­tors and auto­matic device con­fig­u­ra­tion.

Clear customer benefits

This tech­nology, which enables con­trol units and field sen­sors to be con­nected quickly and easily, is not an end in itself, but pro­vides the user with tan­gible – and imme­diate – ben­e­fits. For example, it is pos­sible to access emer­gency stop switches, push­but­tons and LED dis­plays via a single con­trol instance – a Safety PLC. This cen­tral­i­sa­tion enables an ad-hoc response through imme­diate diag­nos­tics, should any faults occur. With IO-Link Safety, you always have a clear overview of costs. With intel­li­gent series con­nec­tion, it is now pos­sible to con­nect sev­eral devices easily via just a single port. A typ­ical example: on the IO-Link Safety Master, only a single port is required to con­nect the con­trol unit PIT­gatebox. If addi­tional sen­sors such as safety switches or guard locking devices are then inte­grated in series, all com­mu­ni­ca­tion con­tinues to occur via this single port – it’s clear, effi­cient and there’s no need for addi­tional wiring. The fact that even com­plex plants such as con­veyors can be com­mis­sioned much more quickly is another eco­nomic advan­tage – because IO-Link Safety sim­pli­fies instal­la­tion and makes the com­mu­ni­ca­tion struc­ture less error-prone.

In short: the pur­pose of con­veyors is to run – without down­times. Shorter com­mis­sioning time is only one aspect; quick device exchange is another. Anyone using IO-Link Safety – tech­ni­cians and main­te­nance per­sonnel – can exchange all devices almost instantly. IO-Link Safety devices self-iden­tify auto­mat­i­cally and adopt para­me­ters directly. This makes them easier to exchange and cuts the number of types – meaning lower storage costs and higher effi­ciency.

Optimised fault diagnostics via IO-Link Safety

As robust con­trol units for safety gate sys­tems, con­trol units such as the PIT­gatebox from Pilz enable com­mands such as acti­vate, stop or acknowl­edge. It should also be pos­sible to trigger or con­trol indi­vidual machine func­tions directly at the point of use, par­tic­u­larly on widely branched plants that extend over a wide area, such as con­veyors. This is because, in this case, swift action on the part of the oper­ator can only be effec­tive if it is part of an imme­diate, coor­di­nated response. It is there­fore an advan­tage that system builders and oper­a­tors can con­nect the PIT­gatebox in series and then inte­grate this oper­ating unit “in series” with IO-Link Safety. But what exactly are the advan­tages? Without IO-Link Safety, the con­trol units must be wired and analysed indi­vid­u­ally. The dif­fer­ence lies in the series con­nec­tion of the con­trol units and in the data diag­nos­tics. Without IO-Link Safety, only cer­tain data is avail­able, such as whether or not an emer­gency stop has been oper­ated. With IO-Link Safety there is sig­nif­i­cantly more diag­nostic data avail­able, such as infor­ma­tion on the status of the device in the field; for example: whether it is flashing or lit, the error code in the event of an error or the item name and number. The infor­ma­tion on the device status tells the oper­ator whether the machine has stopped, for example, and indi­cates what action to take. In this case it is pos­sible to per­form cen­tralised diag­nos­tics on all con­trol units PIT­gatebox. This means that the infor­ma­tion is dis­played cen­trally on the visu­al­i­sa­tion system and not just on the plant.