# Read sensor real to a virtual smart home

**URL:** <https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122>\
**Category:** General\
**Created:** [6 August 2022 20:57 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122 "2022-08-06T20:57:25Z")\
**Posts on this page:** 15\
**Page:** 1

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 20:57 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/1 "2022-08-06T20:57:26Z")

</div>

how i can send a real temperature to the temperature of virtual smart home termostat?  
i sow that i create a inject node with : msg.payload.temperature number 30 it send this value on termosat temperature . so i think its possible but i dont know which function node i must write to do that .  
Someone can help me ? tx

---

<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [6 August 2022 21:17 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/2 "2022-08-06T21:17:04Z")

</div>

Your problem definition is not clear enough. What have you tried? Export and attach your flow.

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 21:23 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/3 "2022-08-06T21:23:31Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/b/1/b11707456578e110d6caa75a3f9f4a675bbdf243.png)

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 21:25 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/4 "2022-08-06T21:25:41Z")

</div>

temp is the sensor of plc maibe now read 27 c° , ciccio is the virtual smart home termostat where the temperature default is 0 . i need to transfer 27 c° into temperature of ciccio termostat

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 21:26 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/5 "2022-08-06T21:26:15Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/c/3c63a0509df0cc64a2a5a3d4d245ff0b8a8ea940.png)

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 21:28 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/6 "2022-08-06T21:28:19Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/6/d6641d7bb51f96cdb448f7f384231cba716136b8.png)

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 21:31 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/7 "2022-08-06T21:31:41Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/3/c3dc68ce0a9bd09025b1b1262cc6b9cbb4778e63.png)  
i need to send 28 to 35

---

<div class="post-metadata">

**Author:** ![craigcurtin](https://avatars.discourse-cdn.com/v4/letter/c/94ad74/32.png) [@craigcurtin](https://discourse.nodered.org/u/craigcurtin)\
**Post date:** [6 August 2022 22:31 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/8 "2022-08-06T22:31:50Z")

</div>

OK trying to understand what you are asking for here

1. You get an incoming temperature from a PLC device - this comes into Node Red
2. You want to get this temperature message and then send it on to your smart thermostat ?

Based on the debug messages you have posted it looks like the thermostat expects the temperature to be in the msg.payload.temperature

Thererefore use a change node to take the msg.payload from the PLC and move it into msg.payload.temperature - no function node needed

Craig

---

<div class="post-metadata">

**Author:** ![Paul-Reed](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/paul-reed/32/66906_2.png) [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)\
**Post date:** [6 August 2022 22:36 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/9 "2022-08-06T22:36:48Z")

</div>

Try `msg.payload.temperature` instead of `msg.payload.value[0]`

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 22:49 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/10 "2022-08-06T22:49:10Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/8/e871e2246e77c6e7db1493f118ce5bce4e25ff2e.png)  
credo di non aver capito scusa ma sono alle prime armi  
paolo non funziona

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [6 August 2022 22:49 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/11 "2022-08-06T22:49:40Z")

</div>

Can u show me how ?

---

<div class="post-metadata">

**Author:** ![craigcurtin](https://avatars.discourse-cdn.com/v4/letter/c/94ad74/32.png) [@craigcurtin](https://discourse.nodered.org/u/craigcurtin)\
**Post date:** [7 August 2022 02:05 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/12 "2022-08-07T02:05:00Z")

</div>

```auto
[{"id":"f91f29146492ae46","type":"debug","z":"d2aef5a196a83414","name":"debug 2","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":780,"y":180,"wires":[]},{"id":"a875c905d420c989","type":"change","z":"d2aef5a196a83414","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"payload.temperature","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":540,"y":160,"wires":[["f91f29146492ae46"]]},{"id":"39d399e3d02d0518","type":"inject","z":"d2aef5a196a83414","name":"","props":[{"p":"payload.temperature","v":"27","vt":"num"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","x":210,"y":160,"wires":[["a875c905d420c989"]]}]

```

You need to watch the into videos to Node Red on youtube and read the basic doco

> **[Node-RED](https://www.youtube.com/c/NodeREDStudio)**
>
> Hi there! This is the official channel of the Node-RED project!
> 
> What's Node-RED? It's an open-source low-code tool for creating event-driven applications. Built on top of node.js, it provides a light-weight, browser-based editor that makes it easy...

Craig

---

<div class="post-metadata">

**Author:** ![dynamicdave](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dynamicdave/32/96_2.png) [@dynamicdave](https://discourse.nodered.org/u/dynamicdave)\
**Post date:** [7 August 2022 02:05 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/13 "2022-08-07T02:05:11Z")

</div>

I think what @Paul-Reed was saying was.. try changing Line-1 of your original flow to...

`var output = msg.payload.temperature;`

---

<div class="post-metadata">

**Author:** ![ivanpesenti](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ivanpesenti/32/85813_2.png) [@ivanpesenti](https://discourse.nodered.org/u/ivanpesenti)\
**Post date:** [7 August 2022 05:54 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/14 "2022-08-07T05:54:11Z")

</div>

grazie ora funziona ma non bisogna usare set ma bensi' MOVE .  
Ancora infinite grazie per aiuto

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [6 October 2022 05:54 UTC](https://discourse.nodered.org/t/read-sensor-real-to-a-virtual-smart-home/66122/15 "2022-10-06T05:54:51Z")

</div>

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.