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Subscribe to the PLC status", "info": "", "x": 170, "y": 40, "wires": [] }, { "id": "a1f0c0de00000101", "type": "inject", "z": "a1f0c0de00000001", "name": "subscribe at start", "props": [ { "p": "payload" } ], "repeat": "", "crontab": "", "once": true, "onceDelay": "2", "topic": "", "payload": "", "payloadType": "str", "x": 140, "y": 140, "wires": [ [ "a1f0c0de00000201", "a1f0c0de00000202", "a1f0c0de00000203", "a1f0c0de00000204", "a1f0c0de00000205" ] ] }, { "id": "a1f0c0de00000201", "type": "OpcUa-Item", "z": "a1f0c0de00000001", "item": "ns=6;s=::FaultDemo:task.status.fault", "datatype": "Boolean", "value": "", "name": "status.fault", "x": 360, "y": 60, "wires": [ [ "a1f0c0de00000301" ] ] }, { "id": "a1f0c0de00000202", "type": "OpcUa-Item", "z": "a1f0c0de00000001", "item": "ns=6;s=::FaultDemo:task.status.conditionActive", "datatype": "Boolean", "value": "", "name": "status.conditionActive", "x": 360, "y": 100, "wires": [ [ "a1f0c0de00000301" ] ] }, { "id": "a1f0c0de00000203", "type": "OpcUa-Item", "z": "a1f0c0de00000001", "item": "ns=6;s=::FaultDemo:task.status.faultCode", "datatype": "UInt16", "value": "", "name": "status.faultCode", "x": 360, "y": 140, "wires": [ [ "a1f0c0de00000301" ] ] }, { "id": "a1f0c0de00000204", "type": "OpcUa-Item", "z": "a1f0c0de00000001", "item": "ns=6;s=::FaultDemo:task.status.faultCount", "datatype": "UInt32", "value": "", "name": "status.faultCount", "x": 360, "y": 180, "wires": [ [ "a1f0c0de00000301" ] ] }, { "id": "a1f0c0de00000205", "type": "OpcUa-Item", "z": "a1f0c0de00000001", "item": "ns=6;s=::FaultDemo:task.status.temperature", "datatype": "Float", "value": "", "name": "status.temperature", "x": 360, "y": 220, "wires": [ [ "a1f0c0de00000301" ] ] }, { "id": "a1f0c0de00000301", "type": "OpcUa-Client", "z": "a1f0c0de00000001", "endpoint": "a1f0c0de000000e1", "action": "subscribe", "deadbandtype": "a", "deadbandvalue": 1, "time": 250, "timeUnit": "ms", "certificate": "n", "localfile": "", "localkeyfile": "", "securitymode": "None", "securitypolicy": "None", "useTransport": false, "maxChunkCount": 1, "maxMessageSize": 8192, "receiveBufferSize": 8192, "sendBufferSize": 8192, "setstatusandtime": false, "keepsessionalive": false, "name": "PLC (subscribe, write)", "applicationName": "", "applicationUri": "", "x": 590, "y": 140, "wires": [ [ "a1f0c0de00000401" ], [ "a1f0c0de00000701" ], [] ] }, { "id": "a1f0c0de00000701", "type": "rbe", "z": "a1f0c0de00000001", "name": "status changes", "func": "rbe", "gap": "", "start": "", "inout": "out", "septopics": false, "property": "status", "topi": "topic", "x": 810, "y": 60, "wires": [ [ "a1f0c0de00000601" ] ] }, { "id": "a1f0c0de00000c02", "type": "comment", "z": "a1f0c0de00000001", "name": "2. Decide: log faults, reset once the condition has gone", "info": "", "x": 870, "y": 260, "wires": [] }, { "id": "a1f0c0de00000102", "type": "inject", "z": "a1f0c0de00000001", "name": "tick 250 ms", "props": [ { "p": "topic", "vt": "str" } ], "repeat": "0.25", "crontab": "", "once": true, "onceDelay": "3", "topic": "tick", "x": 590, "y": 220, "wires": [ [ "a1f0c0de00000401" ] ] }, { "id": "a1f0c0de00000401", "type": "function", "z": "a1f0c0de00000001", "name": "supervisor", "func": "// Supervises the FaultDemo task on the PLC.\n// In: data changes from the OPC UA subscription (msg.topic = NodeId), and a 'tick' every 250 ms\n// Out 1: the reset command, back to the OPC UA client as a write\n// Out 2: log lines, to the log file and the debug sidebar\nconst NS = 'ns=6;s=::FaultDemo:task.';\nconst SETTLE_MS = 1000; // the condition must stay clear this long before we reset\nconst RETRY_MS = 5000; // resend a reset the PLC did not act on\nconst FAULT_DETAIL_MS = 300; // fault, faultCode and faultCount change in one PLC scan but arrive\n // as separate notifications: read the details this long after the edge\nconst FAULT_TEXT = { 1: 'over-temperature', 2: 'forced' };\n\nif (msg.topic !== 'tick' && !String(msg.topic).startsWith(NS + 'status.')) {\n return null; // the subscriptionId message, and the results of our own writes\n}\n\nconst plc = context.get('plc') || {};\nconst now = Date.now();\nconst lines = []; // [time, text]\nlet reset = null;\n\nif (msg.topic !== 'tick') {\n const name = msg.topic.slice(NS.length); // e.g. 'status.fault'\n const before = plc[name];\n plc[name] = msg.payload;\n context.set('plc', plc);\n\n if (name === 'status.fault' && msg.payload !== before) {\n if (msg.payload === true) {\n context.set('faultSince', now);\n context.set('faultDetailDue', now + FAULT_DETAIL_MS);\n // Restart the settle timer: conditionActive may still arrive in a later notification\n context.set('clearSince', plc['status.conditionActive'] === false ? now : null);\n } else if (before === true) {\n const seconds = (now - context.get('faultSince')) / 1000;\n lines.push([now, `CLEARED fault cleared after ${seconds.toFixed(1)} s`]);\n context.set('resetSentAt', null);\n }\n }\n\n if (name === 'status.conditionActive' && msg.payload !== before) {\n context.set('clearSince', msg.payload === false ? now : null);\n if (msg.payload === false && plc['status.fault'] === true) {\n lines.push([now, `OK condition gone, resetting in ${SETTLE_MS} ms`]);\n }\n }\n}\n\n// FAULT: log the details once the rest of the PLC scan has arrived\nconst faultDetailDue = context.get('faultDetailDue');\nif (faultDetailDue && now >= faultDetailDue && plc['status.fault'] === true) {\n context.set('faultDetailDue', null);\n const code = plc['status.faultCode'];\n const temperature = plc['status.temperature'];\n lines.unshift([context.get('faultSince'),\n `FAULT code=${code} (${FAULT_TEXT[code] || 'unknown'}), ` +\n `temperature ${temperature?.toFixed(1)} C, fault #${plc['status.faultCount']}`]);\n}\n\n// RESET: the fault is latched and the condition has stayed clear for SETTLE_MS\nconst clearSince = context.get('clearSince');\nconst resetSentAt = context.get('resetSentAt');\nif (plc['status.fault'] === true && plc['status.conditionActive'] === false &&\n clearSince && now - clearSince >= SETTLE_MS &&\n (!resetSentAt || now - resetSentAt >= RETRY_MS)) {\n context.set('resetSentAt', now);\n reset = { action: 'write', topic: NS + 'command.reset', datatype: 'Boolean', payload: true };\n lines.push([now, 'RESET writing command.reset']);\n}\n\nreturn [reset, lines.map(([time, text]) => ({ payload: `${new Date(time).toISOString()} ${text}` }))];\n", "outputs": 2, "timeout": 0, "noerr": 0, "initialize": "", "finalize": "", "libs": [], "outputLabels": [ "reset command", "log line" ], "x": 810, "y": 160, "wires": [ [ "a1f0c0de00000301" ], [ "a1f0c0de00000501", "a1f0c0de00000602" ] ] }, { "id": "a1f0c0de00000501", "type": "file", "z": "a1f0c0de00000001", "name": "fault-events.log", "filename": "/logs/fault-events.log", "filenameType": "str", "appendNewline": true, "createDir": true, "overwriteFile": "false", "encoding": "none", "x": 1020, "y": 140, "wires": [ [] ] }, { "id": "a1f0c0de00000602", "type": "debug", "z": "a1f0c0de00000001", "name": "log", "active": true, "tosidebar": true, "console": false, "tostatus": false, "complete": "payload", "targetType": "msg", "statusVal": "", "statusType": "auto", "x": 990, "y": 200, "wires": [] }, { "id": "a1f0c0de00000601", "type": "debug", "z": "a1f0c0de00000001", "name": "client status", "active": true, "tosidebar": true, "console": false, "tostatus": false, "complete": "status", "targetType": "msg", "statusVal": "", "statusType": "auto", "x": 1010, "y": 60, "wires": [] }, { "id": "a1f0c0de00000c03", "type": "comment", "z": "a1f0c0de00000001", "name": "3. Manual test: hold a forced fault", "info": "Force ON latches a fault with code 2. 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