Systematic gate guarding!

Because during mate­rial feed, setup or even main­te­nance, for example, humans must interact directly with the machine – and are there­fore in close prox­imity to a poten­tial danger zone. Safety gates, including man­age­ment of access per­mis­sions via a “dig­ital keyring”, offer the nec­es­sary pro­tec­tion. As an automa­tion solu­tion, they pro­vide safety con­cepts that align pro­tec­tion require­ments with effi­ciency spec­i­fi­ca­tions.

Safety gates should offer many types of protection

Safety gate sys­tems are intended to fulfil safety func­tions and must cover dif­ferent types of guard locking reli­ably: from “simple” process guard locking, which is often suf­fi­cient if the machine has no overrun move­ments, through to process pro­tec­tion with inte­grated per­sonnel pro­tec­tion, should the machine keep run­ning after the stop. In short: the appro­priate safe­guard must be con­sid­ered for each safety level.

As a safety expert, this is also the approach taken by Pilz: to pro­vide a selec­tion of dif­ferent com­po­nents which, when com­bined, form a mod­ular safety gate system. In the Pilz system, cus­tomers can choose between the safety locking devices PSENslock and PSEN­m­lock for example, which also form the core of the mod­ular safety gate system. PSENslock covers safe posi­tion mon­i­toring with process guard locking in a single system, while PSEN­m­lock pro­vides safe inter­locking and guard locking for per­sonnel pro­tec­tion – enabling you to manage even the highest cat­e­gory. The name “mod­ular” is no coin­ci­dence: to ensure that the Pilz system can always be used to imple­ment the latest require­ments suc­cess­fully on future appli­ca­tions, Pilz reg­u­larly adds new “mod­ules” to its safety gate system. The latest addi­tion involves the new types of PSEN­m­gate. A longer housing cre­ates space for more con­trol ele­ments, such as push­but­tons and illu­mi­nated but­tons. The focus is there­fore on appli­ca­tions that require a wider range of oper­ating func­tions on the safety gate.

Smart diagnostics a plus point for Safety

With a mod­ular safety gate system such as the one avail­able from Pilz, users can cus­tomise their safety gate pro­tec­tion. That’s because it can be tai­lored to the require­ments of a wide variety of appli­ca­tions. The Pilz system con­tains the appro­priate con­trol units and an optional escape release, for example. Safety gate sys­tems also score points when it comes to diag­nos­tics – pro­longed down­times can be pre­vented quickly and eco­nom­i­cally. In prin­ciple this is achieved via the series con­nec­tion avail­able on sen­sors such as the PSEN­m­lock or the com­pact safety locking device PSEN­m­lock mini. Pro­duc­tivity gains are the result, thanks to smart diag­nos­tics.

How does that work in the Pilz system? If you also use the diag­nostic solu­tion Safety Device Diag­nos­tics (SDD), it is pos­sible to retrieve advanced diag­nostic infor­ma­tion. This means that device prop­er­ties such as the item, product ver­sion and serial number, as well as status infor­ma­tion such as the status of the safety sen­sors them­selves, or the state of their inputs and out­puts, are avail­able quickly and are trans­parent. SDD offers fur­ther advan­tages with regard to safe series con­nec­tion: it enables tar­geted con­trol of indi­vidual sen­sors. Or rather, pre­cise diag­nos­tics for the gates: which ones may be unlocked and opened after shut­down? This is highly rel­e­vant in plants where main­te­nance work is pending, for example. The reverse sce­nario would not be good: all safety gates con­nected in series would open at once if the unlock func­tion were requested – with all the poten­tial risks that would entail.

Industrial Security is another key for Safety

Mod­ular safety gate sys­tems not only allow tailor-made solu­tions – par­tic­u­larly when com­pared with safety switches – but, with the appro­priate expan­sions, also com­bine Safety and Indus­trial Secu­rity in a single system. This added secu­rity is pos­sible because access per­mis­sion is con­sid­ered at the same time. It pre­vents safety mea­sures from being defeated to (sup­pos­edly) make the work easier.

Essen­tially, these are intu­itive oper­ator sys­tems, with which users can also imple­ment Secu­rity: mod­ules for access per­mis­sion are inte­grated into modern safety gate sys­tems such as those avail­able from Pilz, to ensure that only autho­rised per­sons gain access to the appli­ca­tion, i.e. safety gate mon­i­toring and access con­trol are com­bined. For example, the mod­ular safety gate system is oper­ated via a secu­rity-enabled push­button unit: the push­button unit PIT­gatebox is avail­able in var­ious pre-con­fig­ured ver­sions with com­bi­na­tions of push­but­tons, key switches and E‑STOP push­but­tons. As an option, the reader unit for per­mis­sion man­age­ment can already be inte­grated into this con­trol unit. Indi­vidual per­mis­sion is stored on a coded RFID key, which users can use to authen­ti­cate them­selves on the safety gate. In the Pilz system, the key is read in the reader unit PITreader; access is enabled if the appro­priate per­mis­sion is present. This is a clear Secu­rity ben­efit, as it’s pos­sible to ensure that only autho­rised per­sons have access to the plant, based on the qual­i­fi­ca­tion and func­tion of the employees. This clearly shows that when the safety gate system pro­vides Secu­rity along­side Safety, it pro­tects the machine from misuse or manip­u­la­tion, thereby pre­venting unwanted down­times.

Gate management – a comprehensive approach

The signs were there: users always ben­efit when they use com­plete sys­tems for safety gate guarding. When classic “safe guard locking” is com­bined with the “func­tions of con­trol ele­ments”, that’s the state of the art. At Pilz, the safety gate system PSEN­m­gate com­bines the classic safety locking device PSEN­m­lock with the con­trol ele­ments of the push­button unit PIT­gatebox in one com­pact, com­plete package. Its core com­pe­tence of safe guard locking secures the process on acces­sible safety gates as well as covers and flaps, and pro­tects the oper­ator, on enclosed robot appli­ca­tions for example. But not only here – PSEN­m­gate ensures com­plete safety on a wide range of plant and machinery.

Con­clu­sion: mod­ular safety gate sys­tems lend them­selves to com­plete gate appli­ca­tions. With com­pre­hen­sive sys­tems such as these, appli­ca­tions can be imple­mented flex­ibly and indi­vid­u­ally by com­bining indi­vidual com­po­nents. If these mod­ular sys­tems com­bine safety gate mon­i­toring with access con­trol, then the result will be indi­vidual safety gate solu­tions, which can effi­ciently manage access to the machine.