[{"data":1,"prerenderedAt":377},["ShallowReactive",2],{"site-settings":3,"products":40,"site-navigation":60,"pilot":149,"page-opc-ua":253},{"id":4,"areaServed":5,"contactAddress":6,"contactEmail":11,"contactPhone":12,"description":13,"entity":14,"expertise":21,"extension":26,"footerNote":27,"meta":28,"privacyEmail":27,"responsePromise":29,"shareImage":30,"siteName":32,"social":33,"stem":37,"tagline":38,"__hash__":39},"settings\u002Fsettings.yml","United Kingdom",[7,8,9,10],"37 Southfield Drive","Hull","HU14 3DU","UK","enquiries@opcela.co.uk","+44 7359 857344","Opcela builds modern software for industry, so that the people running a production line have tools as good as everything else they use. Tell us about your operations.",{"legalName":15,"companyNumber":16,"registeredIn":17,"registeredAddress":18,"vatNumber":20},"OPCELA SOFTWARE LTD","17403873","England and Wales",[7,19,9],"North Ferriby","529 5939 40",[22,23,24,25],"Alarm notification software","Quality management software for manufacturing","Bespoke software development","OPC UA","yml",null,{},"We reply to every enquiry within one working day.",{"src":31,"alt":32},"\u002Fsocial-share.png","Opcela",[34],{"label":35,"url":36},"LinkedIn","https:\u002F\u002Fwww.linkedin.com\u002Fcompany\u002Fopcela-software","settings","Data, Made Simple","Z18be4cNn35CqZIbs0V2XeJSICx7wTzL_gx7HbCdpD0",[41,53],{"path":42,"title":43,"summary":44,"order":45,"eyebrow":23,"image":46,"features":27,"callToAction":50},"\u002Fproducts\u002Fopcela-quality","Opcela Quality","Quality approvals raised from live process data, on your own hardware.",10,{"src":47,"dark":48,"alt":49},"\u002Fimages\u002Fproducts\u002Fopcela-quality-enterprise-dashboard.png","\u002Fimages\u002Fproducts\u002Fopcela-quality-enterprise-dashboard-dark.png","A screenshot of the Opcela Quality Enterprise dashboard for a fictional bakery, filled with generated data: four headline figures for the quarter, a Pareto chart of interlock downtime by area, and monthly charts of decisions by outcome, average time to decision and automated actions taken",{"label":51,"to":52},"Talk to us","\u002Fcontact",{"path":54,"title":55,"summary":56,"order":57,"eyebrow":58,"image":27,"features":27,"callToAction":59},"\u002Fproducts\u002Fbespoke-software","Bespoke Software","Software written to fit a process when nothing off the shelf fits.",20,"Custom software for engineering sites",{"label":51,"to":52},{"announcement":27,"primary":61,"callToAction":82,"footer":85,"motionControl":125,"legal":128},[62,72,77],{"label":63,"external":64,"items":65,"attributes":27},"Products",false,[66,69],{"label":43,"to":42,"external":64,"items":67,"attributes":68},[],{"to":42},{"label":55,"to":54,"external":64,"items":70,"attributes":71},[],{"to":54},{"label":73,"to":74,"external":64,"items":75,"attributes":76},"Case studies","\u002Fcase-studies",[],{"to":74},{"label":78,"to":79,"external":64,"items":80,"attributes":81},"About","\u002Fabout",[],{"to":79},{"label":51,"to":52,"external":64,"items":83,"attributes":84},[],{"to":52},[86,94,112],{"heading":63,"links":87},[88,91],{"label":43,"to":42,"external":64,"items":89,"attributes":90},[],{"to":42},{"label":55,"to":54,"external":64,"items":92,"attributes":93},[],{"to":54},{"heading":95,"links":96},"Company",[97,100,103,107],{"label":78,"to":79,"external":64,"items":98,"attributes":99},[],{"to":79},{"label":73,"to":74,"external":64,"items":101,"attributes":102},[],{"to":74},{"label":104,"to":52,"external":64,"items":105,"attributes":106},"Contact",[],{"to":52},{"label":108,"to":109,"external":64,"items":110,"attributes":111},"Pilot programme","\u002Fpilot",[],{"to":109},{"heading":113,"links":114},"Reading",[115,120],{"label":116,"to":117,"external":64,"items":118,"attributes":119},"Quality records in a spreadsheet","\u002Fquality-records-in-a-spreadsheet",[],{"to":117},{"label":121,"to":122,"external":64,"items":123,"attributes":124},"OPC UA explained","\u002Fopc-ua",[],{"to":122},{"pause":126,"resume":127},"Pause animations","Resume animations",[129,134,139,144],{"label":130,"to":131,"external":64,"items":132,"attributes":133},"Privacy notice","\u002Flegal\u002Fprivacy-notice",[],{"to":131},{"label":135,"to":136,"external":64,"items":137,"attributes":138},"Cookies and storage","\u002Flegal\u002Fcookies-and-storage",[],{"to":136},{"label":140,"to":141,"external":64,"items":142,"attributes":143},"Terms of use","\u002Flegal\u002Fterms-of-use",[],{"to":141},{"label":145,"to":146,"external":64,"items":147,"attributes":148},"Accessibility","\u002Flegal\u002Faccessibility-statement",[],{"to":146},{"id":150,"banner":151,"extension":26,"form":157,"founder":230,"meta":233,"modal":234,"places":244,"reason":246,"status":247,"stem":250,"terms":251,"__hash__":252},"pilot\u002Fpilot.yml",{"show":152,"lead":153,"leadWithPlacesTaken":154,"link":155},true,"Only {total} pilot places for manufacturers replacing paper checks","Only {left} of {total} pilot places left for manufacturers replacing paper checks",{"label":156,"to":109},"Apply now",{"heading":158,"intro":159,"headingWhenFull":160,"introWhenFull":161,"fields":162,"optionalLabel":218,"privacyIntro":219,"nextStep":220,"submit":221,"errorSummary":224,"sent":225,"failed":226,"subject":227,"subjectWhenFull":228,"notGiven":229},"Apply for a place","Only {left} places are available, because that is all we can handle right now, so apply now. It takes about two minutes. We read every application ourselves, and we reply to applications within 2 working days, then arrange everything around your site's schedule.","Register interest for the next round","Every place is taken. Leave your details and we will be in touch when the next round opens.",{"name":163,"email":166,"company":171,"jobTitle":173,"phone":176,"site":179,"sector":183,"staff":193,"brcgs":200,"firstCheck":209,"recording":212},{"label":164,"missing":165},"Full name","Enter your full name, so we know who we are replying to.",{"label":167,"help":168,"missing":169,"malformed":170},"Work email","This is where the reply goes.","Enter your work email address, so we have somewhere to reply to.","This does not look like an email address. Check it reads like name@company.com, with one @ and a dot in the part after it.",{"label":95,"missing":172},"Enter the name of your company.",{"label":174,"missing":175},"Job title","Enter your job title, so we know who we will be talking to.",{"label":177,"help":178},"Phone","Only if you would rather we rang you.",{"label":180,"help":181,"missing":182},"Site town or postcode","Where the site the pilot would run on is.","Enter the town or postcode of the site, so we know where it is.",{"label":184,"choose":185,"options":186,"missing":192},"What does the site make?","Choose one",[187,188,189,190,191],"Food and drink","Packaging","Chemicals or pharmaceuticals","Engineering or metalwork","Something else","Choose what the site makes.",{"label":194,"choose":185,"options":195,"missing":199},"Roughly how many people work on the site?",[196,197,198],"Under 50","50–249","250+","Choose roughly how many people work on the site.",{"label":201,"choose":185,"options":202,"missing":208},"Is the site audited against a standard?",[203,204,205,206,207],"BRCGS","ISO 9001","Another standard","Working towards one","Not at the moment","Choose whether the site is audited against a standard.",{"label":210,"help":211},"Which check would you most like off paper?","A line is plenty, for example a label check or a metal detector check.",{"label":213,"choose":185,"options":214},"How are quality checks recorded today?",[215,216,217],"Mostly paper","Mix of paper and digital","Mostly digital","Optional","Opcela uses these details to assess your application, arrange the Quality Evidence Walk and, if every place is taken, tell you when the next round opens. Our lawful basis is legitimate interests, so there is nothing to tick and you can object at any time.","Step one is a free half-day Quality Evidence Walk. Keep the write-up either way.",{"label":158,"labelWhenFull":222,"pending":223},"Register interest","Sending","There is a problem with this form","Thanks. We will be in touch within 2 working days to arrange a call at a time that suits you.","Your application could not be sent. Check your connection and try again, or write to us directly at the address below.","Pilot programme application","Pilot programme, interest in the next round","Not given",{"heading":231,"intro":232},"Who you will work with","You work directly with the person who built Opcela Quality, from the first conversation to your first scan.",{},{"show":152,"eyebrow":235,"heading":236,"text":240,"scarcity":241,"action":242,"close":243},"Opcela Quality pilot programme",{"lead":237,"mark":238,"second":239},"Only {total} FREE","FREE","Pilot Places","We are taking on {total} manufacturing sites to trial Opcela Quality: automated checks and handheld scanning in place of paper check sheets.","Only {left} places available, because that is all we can handle right now. Places are offered by fit, not first come first served.",{"label":158,"to":109},"Close",{"total":245,"left":245},5,"Free, because handheld scanning is new and we want five sites to shape it with us. If it works for you, we would like to tell others about it in a case study.",{"placesTaken":248,"full":249},"Only {left} of {total} places available.","All pilot places are taken. Register interest for the next round.","pilot","No charge for the software, set-up or training. Your site supplies the handheld scanners and IT access.","J4RsfzrpxzbIKCVmyMuGX6uqkQ2pHzhBqqm_lzeTtnE",{"id":254,"title":255,"body":256,"caseStudies":27,"caseStudy":27,"contact":366,"description":369,"extension":370,"eyebrow":121,"hero":27,"image":27,"intro":371,"listed":64,"meta":372,"navigation":152,"path":122,"products":27,"published":64,"seo":373,"statement":27,"stem":375,"team":27,"__hash__":376},"pages\u002Fopc-ua.md","OPC UA, and what Opcela Quality does with it",{"type":257,"value":258,"toc":355},"minimark",[259,264,268,271,274,278,290,295,299,302,305,309,312,316,319,322,326,329,332,336,342,345,352],[260,261,263],"h2",{"id":262},"what-opc-ua-is","What OPC UA is",[265,266,267],"p",{},"OPC UA stands for OPC Unified Architecture. It is a specification from the OPC Foundation,\nalso published as IEC 62541, for how industrial equipment and software describe data to\neach other and exchange it. A controller, a drive, a gateway or a piece of software that\nserves it can be read by any client that speaks it, without either side knowing anything\nabout the other's make.",[265,269,270],{},"It is the successor to OPC Classic, the earlier family of specifications, Data Access and\nHistorical Data Access among them. Those were built on Microsoft's COM and DCOM, which tied\nthem to Windows and made them awkward to run across a network. OPC UA was written to be\nindependent of any operating system and to carry its own security, and it is the form new\ncontrollers and gateways commonly expose.",[265,272,273],{},"The specification is in parts, each covering one thing: the address space (Part 3), the\nservices a client can call (Part 4), data access (Part 8), historical access (Part 11) and\npublish-subscribe (Part 14) are the ones a reader of this page is most likely to meet.\nCompanion specifications, written with industry bodies, add standard models for particular\nkinds of equipment on top.",[260,275,277],{"id":276},"servers-clients-nodes-and-tags","Servers, clients, nodes and tags",[265,279,280,281,285,286,289],{},"Over a session, everything in OPC UA is one of two roles. A ",[282,283,284],"strong",{},"server"," holds the data and\ndescribes it; a ",[282,287,288],{},"client"," connects to a server, reads what it describes, and asks to be\ntold when it changes. A controller with a built-in server, a gateway in front of older kit,\nan OPC server product that translates another protocol, and a supervisory system where it\nexposes one, are all servers. Opcela Quality is a client.",[291,292],"points",{":items":293,"layout":294},"[{\"name\":\"The address space\",\"detail\":\"What a server exposes is a set of nodes, joined by references into a structure a client can browse. A folder is a node, a machine is a node, a value on that machine is a node. The server describes its own structure, so a client can discover what is there rather than being told in advance.\"},{\"name\":\"A tag is a variable node\",\"detail\":\"What a plant calls a tag, the specification calls a variable: a node that holds a value. Every value comes with a data type, a timestamp, and a status code saying whether the reading is good, bad or uncertain. That status code is what the searches for an OPC UA quality code are about; it is a flag on a reading, and it has nothing to do with quality management.\"},{\"name\":\"A node id\",\"detail\":\"Each node is addressed by a node id, which is a namespace and an identifier inside it. The identifier can be a number, a string, a GUID or an opaque value, and the namespace says which vocabulary it belongs to, so the standard's own nodes and a maker's own can each have a node numbered 1001 in the same server without colliding.\"},{\"name\":\"A session\",\"detail\":\"A client opens a secure channel to a server's endpoint, then a session on top of it, and everything else happens inside that session: browsing, reading, writing, calling a method, or subscribing. The session is what the server authenticates and what it closes when the client goes away.\"}]","stacked",[260,296,298],{"id":297},"subscriptions-and-why-a-client-does-not-poll","Subscriptions, and why a client does not poll",[265,300,301],{},"The part of OPC UA that matters most for monitoring is the subscription. A client creates a\nsubscription on its session, adds the nodes it cares about as monitored items, and states\nhow often the server should sample each one and how often it should publish. From then on\nthe server sends the client what has changed, and only what has changed, at the publishing\ninterval. A client can also set a deadband, so a value that flickers by a fraction is not\nreported at all.",[265,303,304],{},"That is different from polling, where a client reads every value on a timer whether or not\nit has moved. A subscription costs less on the network, puts the sampling where the value\nlives, and reports every change the server sampled rather than whichever value happened to\nbe there when the client asked. It is how Opcela Quality reads a tag.",[260,306,308],{"id":307},"security","Security",[265,310,311],{},"Every OPC UA server publishes one or more endpoints, and each endpoint states the security\nit offers: a security policy, which is the set of algorithms, and a security mode, which\nis whether messages are signed, signed and encrypted, or neither. Client and server\nidentify each other with X.509 digital certificates, and a server will refuse a client\npresenting one it has not been told to trust. A user can then be authenticated on the\nsession in their own right, by name and password or by a digital certificate of their own.\nThe usual\ntransport is the binary encoding over TCP, and the port registered for it is 4840.",[260,313,315],{"id":314},"opc-ua-beside-the-other-protocols","OPC UA beside the other protocols",[265,317,318],{},"The comparisons people search for most are with the two protocols they are most likely to\nhave on site already.",[291,320],{":items":321,"layout":294},"[{\"name\":\"OPC UA and Modbus\",\"detail\":\"Modbus is far older and far simpler. It moves sixteen-bit registers and single-bit coils from a device that has no way of saying what a register means, what type it holds, or when it last changed, and the base protocol has no security. Everything about the meaning of the data lives in a spreadsheet beside the project. OPC UA carries the name, the type, the timestamp and the status with every value, and secures the connection. Plenty of equipment speaks both, and a gateway or an OPC server product is the usual way to bring a Modbus device into an OPC UA address space.\"},{\"name\":\"OPC UA and MQTT\",\"detail\":\"MQTT is a publish-subscribe messaging protocol. A publisher sends a message to a broker under a topic, and every subscriber to that topic receives it. It is light and it scales well, and it says nothing at all about what is inside the message: the payload is whatever the publisher chose, so two senders need a separate agreement on its shape. Sparkplug B is one such agreement, fixing the topic layout and the payload format on top of MQTT. OPC UA defines the data model as well as the transport, and since Part 14 it can publish over MQTT itself. The two are not rivals so much as answers to different questions: one is a message bus, the other is a description of the plant.\"},{\"name\":\"OPC UA and OPC DA\",\"detail\":\"OPC DA is the classic Data Access interface OPC UA replaced. It does the same job of reading and writing live values, but it is a Windows COM interface, so it needs a Windows machine at each end and DCOM configured between them. A wrapper or a gateway can present a DA server as a UA one, which is how a great deal of older kit is still read today.\"}]",[260,323,325],{"id":324},"where-it-sits-in-the-plant","Where it sits in the plant",[265,327,328],{},"The usual way to draw a plant is in levels, from the process at the bottom to the business\nsystems at the top, in the arrangement the ISA-95 standard describes: the physical process\nat level zero, the sensors and actuators at level one, the controllers at level two,\noperations management at level three, and planning at level four. OPC UA is one of the\nways level two exposes what it knows, and one of the ways the levels above read it.",[265,330,331],{},"Opcela Quality reads from that layer and does not take it over. The control layer stays\nwith whoever holds it; the software is a client of it.",[260,333,335],{"id":334},"what-opcela-quality-does-with-it","What Opcela Quality does with it",[265,337,338,341],{},[339,340,43],"a",{"href":42}," is an OPC UA client that watches tag values and\ndoes something when they meet a condition. You choose the tags and set the condition on\nscreen, a tag going high, for instance. The software subscribes to those tags and evaluates\nthe condition itself, on the values it receives, so the server has to do nothing more than\nserve them.",[265,343,344],{},"When the condition is met, a workflow runs. One named person is told, by SMS, by WhatsApp or\nby email to the details on their own profile, and asked to approve. The approval is\nrecorded, and the reports and signoff certificates come out of that record. A condition on\na tag is how an alarm is expressed here: a tag going high is an alarm, and what follows it\nis the half this product is about.",[346,347,349],"callout",{"title":348},"What you are left holding",[265,350,351],{},"A live dashboard, PDF reports, signoff certificates, and an audit trail that is immutable\nand append-only. Nothing in the application edits or deletes an entry. It runs on your own\nhardware.",[265,353,354],{},"Two things it is not, so that nobody has to ask. It is not a historian: it does not exist to\nstore and serve the history of every tag, which is what Part 11 of the specification and a\nhistorian product are for. It keeps the record of what it raised and what was decided about\nit. And it is not tied to any maker of equipment. It speaks OPC UA, so it\ntalks to whatever exposes an OPC UA server, whether that is a controller with one built in,\na supervisory system, or an OPC server product standing in front of older kit.",{"title":356,"searchDepth":357,"depth":357,"links":358},"",2,[359,360,361,362,363,364,365],{"id":262,"depth":357,"text":263},{"id":276,"depth":357,"text":277},{"id":297,"depth":357,"text":298},{"id":307,"depth":357,"text":308},{"id":314,"depth":357,"text":315},{"id":324,"depth":357,"text":325},{"id":334,"depth":357,"text":335},{"heading":367,"action":368},"Tell us about your operations",{"label":51,"to":52},"What OPC UA is, how a server, a node, a tag and a subscription fit together, and how Opcela Quality monitors OPC UA tag values and acts on a condition you set.","md","The protocol plant equipment uses to talk to software, in plain words: servers, tags, subscriptions and security. Then what Opcela Quality does with the values it reads.",{},{"title":374,"description":369},"What is OPC UA, and what we do with it","opc-ua","qz42fHZsteeicnjPkRi-4IGecl9vbsTKwbUASyBY7MA",1791821594035]