worked like a charm 
With the caveat that I am using Node Red 3, there is an and logic node: BooleanLogicUltimateNode
I can’t be certain but I think it is included by default in NR3?
Here is an example flow diagram I am using it in:
The Gate 2 node in the above image will set the ouput to true if either of the contact sensors input to it are opened.
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I am also using the Boolean Logic Ultimate node - it’s a great way to do multi-sensor motion lighting. Here’s an example where I tie three motion sensors and a door contact sensor together to make sure that the lights in the basement hallway come on when needed.
I forget about the various boolean nodes, but personally would never recommend their use to anyone who doesn’t already have a strong grasp of how NR logic works/flows.
There isn’t anything actually wrong with using them that i can think of, but being able to implement this kind of logic on your own will make troubleshooting and understanding future issues, not to mention shared flows, much simpler.
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I would argue the opposite. Node-red was new to me when my Core arrived on my doorstep. As someone with a background in “older” technologies, I immediately took to the simple node that could give me AND, OR, and XOR gate functionality. Tidies things up nicely, where I find the converse (chaining multiple switch nodes) to require far too much thinking and double-checking: what did I assign to the output terminals? Am I comparing strings, numbers, booleans? To each their own, I suppose… still looking for a use case for the XOR terminal of the Boolean Logic Ultimate node - seems superfluous. The AND and OR gates are awesome, though.
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I have NEVER understood this concept. I read about it, try it … it breaks or gives me results that I didn’t expect or understand. Maybe one day when we have a few minutes, you could explain that to me and others. Never too late to learn abut them.
This is part of why I love NR, there are so many ways to do the same thing, and there is no “right” or “wrong” way to do something, just ways to do it
MY biggest issue with starting out with the boolean nodes, aside from the spotty performance history with XOR operations, is that It can keep you from having to fully understand and grasp some important concepts in NR, and without you even realizing it you will be limiting your automations potential.
Sure use it to get started, help simplify your flows and make them easier to troubleshoot and understand.
But PLEASE don’t do yourself a disservice, make sure you still take the time to understand the logic and structures behind the manual way of doing it!!!
This goes for pretty much any node in NR. Use them to make your life easier, that’s their job, but make sure you take the time to understand how and why the node does what it does. You wont regret it!
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Think of it like digital circuit design - after covering all the background on transistors and impedances and all that good stuff, you get to the first real practical devices: flip-flops, AND, and OR gates. These are boolean comparitors: inputs are either on/off (true/false) and the output is similarly binary.
In words, and AND gate gives you a true value if all inputs are true. For any other combination of inputs the output value is false. Here’s a picture I stole from the Internet:
An OR gate will give you a true output when ANY of the inputs is true, up to and including the case where all inputs are true. The only time an OR gate will give a false output is if all inputs are false. Another stolen picture:
The AND and OR gates don’t change in concept with a larger number of inputs: AND gives a true output only when all inputs are true. OR gives a true output when any input is true.
Let’s transition to motion lighting: I have three motion sensors and a door contact sensor for my basement hallway zone. That hallway is windowless and pitch black if the lights are off. Motion sensors are positioned to detect anyone entering the zone, so that means that I want to turn on the lights any time motion is detected - I don’t care which motion sensor trips, I want the lights on. Same with the door sensor - someone is coming into the hall from the garage and the lights need to be on. This is the perfect scenario for an OR gate: if sensor 1 OR sensor 2 OR sensor 3 OR sensor 4 are true, flip on the lights.
The AND gate could be used (poorly, imo) for occupancy sensing: if this sensor AND that sensor trip, someone must be in the area, so do X. Too reliant on both sensors working properly. You could use a flow variable or a global as one input to an AND, for example: if someone is present at home (use whatever means you have to figure this out), a global variable is set true. Now add an AND gate to your motion lighting: at the end of the sequence, where you’re commanding the lights to turn on, put the AND gate. One input is the lights on command “true” and the other input is the presence state “true”. The lights will only come on if the normal motion lighting sequence triggers it AND somebody is home. Pets not allowed.
XOR, NAND, and NOR are other common gate types that you could dig into, but I think home automation tasks probably wouldn’t need them. Was this helpful in any way?
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Hi there.
I’ve been trying to do the very same and have been struggling to get it to work. I have the boolean used installed.
Would you mind sharing the flow so I can see how you have done it.
Many thanks.
My very first flow export, so I’m uncertain if I did it right or not. Let me know if this works:
[{"id":"75af6a15836294e0","type":"comment","z":"474cb7d41eb3ceb5","name":"Basement Hallway Light","info":"","x":380,"y":480,"wires":[]},{"id":"fbf8ec15af1d0ecb","type":"mqtt in","z":"474cb7d41eb3ceb5","name":"MS-2","topic":"zwave/Basement/Basement_Hallway_MS-2/48/0/Motion","qos":"2","datatype":"auto-detect","broker":"a99b67b86f3f3e3e","nl":false,"rap":true,"rh":0,"inputs":0,"x":70,"y":580,"wires":[["351b2a6ddf5faaaa"]]},{"id":"351b2a6ddf5faaaa","type":"change","z":"474cb7d41eb3ceb5","name":"value","rules":[{"t":"set","p":"payload","pt":"msg","to":"payload.value","tot":"msg"},{"t":"set","p":"topic","pt":"msg","to":"MS-2","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":580,"wires":[["64ec30adc2697f2e"]]},{"id":"97300c0e415a41c8","type":"rbe","z":"474cb7d41eb3ceb5","name":"","func":"rbe","gap":"","start":"","inout":"out","septopics":true,"property":"payload","topi":"topic","x":370,"y":540,"wires":[["b39c680b5b5ed8c9"]]},{"id":"9e5a6e3e9c17040e","type":"zigbee2mqtt-in","z":"474cb7d41eb3ceb5","name":"MS-1","server":"ac659ac3d7fc300e","friendly_name":"Basement Hallway MS-1 (SNZB-03)","device_id":"0x00124b001f44ebf8","state":"occupancy","outputAtStartup":true,"filterChanges":false,"enableMultiple":false,"x":70,"y":540,"wires":[["93c7656ac2313c99"]]},{"id":"93c7656ac2313c99","type":"change","z":"474cb7d41eb3ceb5","name":"Topic","rules":[{"t":"set","p":"topic","pt":"msg","to":"MS-1","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":540,"wires":[["97300c0e415a41c8"]]},{"id":"64ec30adc2697f2e","type":"rbe","z":"474cb7d41eb3ceb5","name":"","func":"rbe","gap":"","start":"","inout":"out","septopics":true,"property":"payload","topi":"topic","x":370,"y":580,"wires":[["b39c680b5b5ed8c9"]]},{"id":"126a64d36474acf2","type":"rbe","z":"474cb7d41eb3ceb5","name":"","func":"rbe","gap":"","start":"","inout":"out","septopics":true,"property":"payload","topi":"topic","x":370,"y":620,"wires":[["b39c680b5b5ed8c9"]]},{"id":"b39c680b5b5ed8c9","type":"BooleanLogicUltimate","z":"474cb7d41eb3ceb5","name":"MotionDoor","payloadPropName":"payload","filtertrue":"both","persist":true,"sInitializeWith":"false","triggertopic":"trigger","outputtriggeredby":"all","inputCount":"4","topic":"BMTmotion","restrictinputevaluation":true,"delayEvaluation":0,"x":560,"y":600,"wires":[[],["952bb276a749f54a"],[]]},{"id":"054acfd1fd83e7ba","type":"mqtt in","z":"474cb7d41eb3ceb5","name":"MS-3","topic":"zwave/Basement/Basement_Hallway_MS-3/48/0/Motion","qos":"2","datatype":"auto-detect","broker":"a99b67b86f3f3e3e","nl":false,"rap":true,"rh":0,"inputs":0,"x":70,"y":620,"wires":[["8c880437b185bdde"]]},{"id":"8c880437b185bdde","type":"change","z":"474cb7d41eb3ceb5","name":"value","rules":[{"t":"set","p":"payload","pt":"msg","to":"payload.value","tot":"msg"},{"t":"set","p":"topic","pt":"msg","to":"MS-3","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":620,"wires":[["126a64d36474acf2"]]},{"id":"12d831310d207a4c","type":"mqtt in","z":"474cb7d41eb3ceb5","name":"Basement Door","topic":"zwave/Basement/Basement_Door_Entry_Sensor/48/0/Any","qos":"2","datatype":"auto-detect","broker":"a99b67b86f3f3e3e","nl":false,"rap":true,"rh":0,"inputs":0,"x":100,"y":660,"wires":[["ef4dec473d7d1b37"]]},{"id":"ef4dec473d7d1b37","type":"change","z":"474cb7d41eb3ceb5","name":"value","rules":[{"t":"set","p":"payload","pt":"msg","to":"payload.value","tot":"msg"},{"t":"set","p":"topic","pt":"msg","to":"Basement_Door","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":660,"wires":[["c9fcb2d1f332856c"]]},{"id":"c9fcb2d1f332856c","type":"rbe","z":"474cb7d41eb3ceb5","name":"","func":"rbe","gap":"","start":"","inout":"out","septopics":true,"property":"payload","topi":"topic","x":370,"y":660,"wires":[["b39c680b5b5ed8c9"]]},{"id":"952bb276a749f54a","type":"rbe","z":"474cb7d41eb3ceb5","name":"","func":"rbe","gap":"","start":"","inout":"out","septopics":true,"property":"payload","topi":"topic","x":730,"y":600,"wires":[["a2dc8204fbb368cc"]]},{"id":"a2dc8204fbb368cc","type":"switch","z":"474cb7d41eb3ceb5","name":"active?","property":"payload","propertyType":"msg","rules":[{"t":"true"},{"t":"false"}],"checkall":"true","repair":false,"outputs":2,"x":560,"y":540,"wires":[["4e04389e0fbc5306","a2e588cb49418997"],["a44d801ffb56c27f"]]},{"id":"4e04389e0fbc5306","type":"change","z":"474cb7d41eb3ceb5","name":"STOP","rules":[{"t":"delete","p":"payload","pt":"msg"},{"t":"set","p":"payload","pt":"msg","to":"stop","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":690,"y":500,"wires":[["a44d801ffb56c27f"]]},{"id":"a44d801ffb56c27f","type":"stoptimer3","z":"474cb7d41eb3ceb5","duration":"5","durationType":"num","units":"Minute","payloadtype":"num","payloadval":"0","name":"5 minute timer","x":840,"y":520,"wires":[["a2e588cb49418997"],[]]},{"id":"a2e588cb49418997","type":"switch","z":"474cb7d41eb3ceb5","name":"True?","property":"payload","propertyType":"msg","rules":[{"t":"true"},{"t":"false"}],"checkall":"true","repair":false,"outputs":2,"x":870,"y":580,"wires":[["4218d056cc733269"],["774b5f492b9b771c"]]},{"id":"89650f2a773344c2","type":"mqtt out","z":"474cb7d41eb3ceb5","name":"Send to switch","topic":"zwave/Basement/Basement_Hallway_Light/37/0/targetValue/set","qos":"1","retain":"true","respTopic":"","contentType":"","userProps":"","correl":"","expiry":"","broker":"a99b67b86f3f3e3e","x":1240,"y":580,"wires":[]},{"id":"774b5f492b9b771c","type":"change","z":"474cb7d41eb3ceb5","name":"Reset payload false","rules":[{"t":"delete","p":"payload","pt":"msg"},{"t":"set","p":"payload","pt":"msg","to":"false","tot":"bool"}],"action":"","property":"","from":"","to":"","reg":false,"x":1050,"y":600,"wires":[["89650f2a773344c2"]]},{"id":"4218d056cc733269","type":"change","z":"474cb7d41eb3ceb5","name":"Reset payload true","rules":[{"t":"delete","p":"payload","pt":"msg"},{"t":"set","p":"payload","pt":"msg","to":"true","tot":"bool"}],"action":"","property":"","from":"","to":"","reg":false,"x":1050,"y":560,"wires":[["89650f2a773344c2"]]},{"id":"a99b67b86f3f3e3e","type":"mqtt-broker","name":"Core MQTT","broker":"10.10.2.1","port":"1883","clientid":"","autoConnect":true,"usetls":false,"protocolVersion":"4","keepalive":"60","cleansession":true,"birthTopic":"","birthQos":"0","birthPayload":"","birthMsg":{},"closeTopic":"","closeQos":"0","closePayload":"","closeMsg":{},"willTopic":"","willQos":"0","willPayload":"","willMsg":{},"userProps":"","sessionExpiry":""},{"id":"ac659ac3d7fc300e","type":"zigbee2mqtt-server","name":"Core z2m","host":"10.10.2.1","mqtt_port":"1883","mqtt_username":"","mqtt_password":"","mqtt_qos":"0","tls":"","usetls":false,"base_topic":"zigbee2mqtt"}]
1 Like
Another significant benefit with using these boolean nodes is that they translate various states to true or false i.e.:
You can use the invert node to toggle the state of the sensor if needed.
IMHO, using the boolean node has made my flow much easier to create and understand; Especially as the boolean nodes shows you the results of all three operations under the node.
4 Likes
Yes, you did it correctly. 
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This is all great information. I would just really like to suggest again we have separate threads for flows instead of one massive topic. At least for the basic get started stuff. It just makes it overwhelming trying to find the info you want.
3 Likes
It imported OK. Thankyou.
Well, I had a look and can confidently say, “I’m completely lost”.
I was sort of on the right track with my original effort but this has just confused me with all these topics and stuff!!! 
As you can tell I’m just learning.
I will keep persevering.
EDIT: On further examination I can see what each node is doing. It is starting to make a bit of sense and I think I may be able to work it out. Thanks again.
2 Likes
We can fire up a teams later on Node-RED if anyone wants to join. Screen recordings or any type are explicitly forbidden.
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I would be able to join anytime after 8pm EST. Would love if someone can go over the fundamentals (like global variables, flow overrides, etc)
I made a few flows and they seem to work, so any input on what to improve would also be great!
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Done, we’ll work in a Teams meeting tonight. Come and go, but don’t leave without saying goodbye. We’ll post a fresh topic with the meeting details later when we fire things up.
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Yeah the topics thing is just a way for the boolean node to distinguish different inputs, since the node doesn’t dynamically create an appropriate # of input terminals. Would be super cool if it did…
Edit: and for those of you wondering, I use the filter node liberally because I’m lazy. I assume my devices will send updates even when there’s no state change, so the filter node is my go-to signal cleanup circuit. I don’t want to trigger more than once for a single valued sensor reading. I haven’t actually verified if this is needed on a per-device basis.
1 Like
Well your flow has filled in a couple of parts I was missing. I now have it working as I want, I think.
Just using 2 motion sensors as a test and sending a pushover message, when sensors go active I get the following messages.
1 active
AND = false
OR = true
XOR = true
2 active
AND = true
OR = true
XOR = false
So I’m assuming I can use the O/P’s as I need.
Either sensor then OR must = true.
If I need both then AND must = true.
For all inactive then I will need OR AND and XOR = false.
I think I can do that.
Any thoughts on my theory?
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Good up to the last line… no need to check the AND or XOR outputs for an all-false condition. The OR gate gives this to you on its own. Glad you got it to this point! It’s pretty smooth sailing once you’ve got the topic-delimited inputs figured out…