Great node! Working like a charm 
and I finally replace my crontab task for monitoring every 10min my RuuviTag+s placed in every room of my house 
If someone is interested, here is my flow. Enjoy!
[
{
"id": "4a8bdd14.b8273c",
"type": "inject",
"z": "a0d43e19.34e2",
"name": "Start BLE scan every 10min",
"topic": "startBLEScan",
"payload": "{ \"scan\": true }",
"payloadType": "json",
"repeat": "600",
"crontab": "",
"once": true,
"x": 210,
"y": 80,
"wires": [
[
"e57b915d.d96dc"
]
]
},
{
"id": "e57b915d.d96dc",
"type": "scan ble",
"z": "a0d43e19.34e2",
"uuids": "",
"duplicates": false,
"name": "",
"x": 590,
"y": 120,
"wires": [
[
"8065e07d.317b18"
]
]
},
{
"id": "8065e07d.317b18",
"type": "ruuvitag",
"z": "a0d43e19.34e2",
"name": "",
"x": 760,
"y": 120,
"wires": [
[
"28a3f1f8.c6ddb6"
]
]
},
{
"id": "6fb8c7d6.e16b18",
"type": "inject",
"z": "a0d43e19.34e2",
"name": "Stop BLE scan every 10min",
"topic": "stopBLEScan",
"payload": "{ \"scan\": false }",
"payloadType": "json",
"repeat": "600",
"crontab": "",
"once": true,
"x": 200,
"y": 160,
"wires": [
[
"f9c4ebfe.f3f47"
]
]
},
{
"id": "3057eda0.382f72",
"type": "debug",
"z": "a0d43e19.34e2",
"name": "",
"active": true,
"console": "false",
"complete": "true",
"x": 1150,
"y": 60,
"wires": []
},
{
"id": "f9c4ebfe.f3f47",
"type": "delay",
"z": "a0d43e19.34e2",
"name": "",
"pauseType": "delay",
"timeout": "10",
"timeoutUnits": "seconds",
"rate": "1",
"nbRateUnits": "1",
"rateUnits": "second",
"randomFirst": "1",
"randomLast": "5",
"randomUnits": "seconds",
"drop": false,
"x": 410,
"y": 160,
"wires": [
[
"e57b915d.d96dc"
]
]
},
{
"id": "28a3f1f8.c6ddb6",
"type": "function",
"z": "a0d43e19.34e2",
"name": "Generate MQTT topic",
"func": "var device = null;\n if (msg.peripheralUuid == \"aaaaaaaaaaaa\") {\n device = \"bedroom1\";\n} else if (msg.peripheralUuid == \"bbbbbbbbbbbb\") { \n device = \"livingroom\";\n} else if (msg.peripheralUuid == \"cccccccccccc\") { \n device = \"kitchen\";\n} else if (msg.peripheralUuid == \"dddddddddddd\") { \n device = \"bathroom\";\n} else if (msg.peripheralUuid == \"eeeeeeeeeeee\") { \n device = \"bedroom2\";\n} else if (msg.peripheralUuid == \"ffffffffffff\") {\n device = \"bedroom3\";\n}\nmsg.topic = device + \"/measurements\";\nreturn msg;",
"outputs": 1,
"noerr": 0,
"x": 960,
"y": 120,
"wires": [
[
"e35e99c4.f1c26",
"3057eda0.382f72"
]
]
},
{
"id": "e35e99c4.f1c26",
"type": "mqtt out",
"z": "a0d43e19.34e2",
"name": "",
"topic": "",
"qos": "",
"retain": "",
"broker": "ec06f45c.253818",
"x": 1150,
"y": 120,
"wires": []
},
{
"id": "ec06f45c.253818",
"type": "mqtt-broker",
"z": "",
"broker": "localhost",
"port": "1883",
"clientid": "",
"usetls": false,
"compatmode": false,
"keepalive": "60",
"cleansession": true,
"willTopic": "",
"willQos": "0",
"willPayload": "",
"birthTopic": "",
"birthQos": "0",
"birthPayload": ""
}
]