# Where change node gets this data?

**URL:** <https://discourse.nodered.org/t/where-change-node-gets-this-data/63823>\
**Category:** General\
**Created:** [12 June 2022 15:03 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823 "2022-06-12T15:03:40Z")\
**Posts on this page:** 11\
**Page:** 1

<div class="post-metadata">

**Author:** ![SeRiusRod](https://avatars.discourse-cdn.com/v4/letter/s/278dde/32.png) [@SeRiusRod](https://discourse.nodered.org/u/SeRiusRod)\
**Post date:** [12 June 2022 15:03 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/1 "2022-06-12T15:03:40Z")

</div>

![imagen](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/6/76e70287740bd2b48b502cbed1295c7d2adec7b4.png)

"Capacity, setpoint" node emits:  
 ![imagen](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/d/6dd52d588d98c8129009255475b73f6957a88a21.png)

Change node has:  
 ![imagen](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/d/4dace606699c168f90924ec4b7d1a3b568719082.png)  
 ![imagen](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/4/c4ccdeaf2a323a37bdba24c76982c003ee4d5754.png)

The next node gets:  
 ![imagen](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/7/978f79ae8057d980be08ecae0fd6c32159cbed09.png)

I'm so confused. Where is getting those numbers? Even the date is wrong. It's picking the local time as UTC.

---

<div class="post-metadata">

**Author:** ![mickym2](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/mickym2/32/36128_2.png) [@mickym2](https://discourse.nodered.org/u/mickym2)\
**Post date:** [12 June 2022 15:09 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/2 "2022-06-12T15:09:03Z")

</div>

I do not understand. So you posted what is in the JSONATA code, so you can directly see, where the numbers came from. So the date came from $millis() etc.

---

<div class="post-metadata">

**Author:** ![SeRiusRod](https://avatars.discourse-cdn.com/v4/letter/s/278dde/32.png) [@SeRiusRod](https://discourse.nodered.org/u/SeRiusRod)\
**Post date:** [12 June 2022 15:09 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/3 "2022-06-12T15:09:10Z")

</div>

A reboot has fixed that output. But I'm still wondering what could cause that.

---

<div class="post-metadata">

**Author:** ![mickym2](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/mickym2/32/36128_2.png) [@mickym2](https://discourse.nodered.org/u/mickym2)\
**Post date:** [12 June 2022 15:11 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/4 "2022-06-12T15:11:29Z")

</div>

If you open the JSONATA editor , you have also a function reference

---

<div class="post-metadata">

**Author:** ![SeRiusRod](https://avatars.discourse-cdn.com/v4/letter/s/278dde/32.png) [@SeRiusRod](https://discourse.nodered.org/u/SeRiusRod)\
**Post date:** [12 June 2022 15:12 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/5 "2022-06-12T15:12:09Z")

</div>

The right values are at the first debug image, that I got from a debug node before the change node.  
The wrong values are the second ones, that I got the same way but after the change node.  
The right battery measurement was 57, not 52. And setpoint was negative. I don't know if the input of a node can "hang" but the battery had 52v early in the morning. 😵‍💫

---

<div class="post-metadata">

**Author:** ![mickym2](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/mickym2/32/36128_2.png) [@mickym2](https://discourse.nodered.org/u/mickym2)\
**Post date:** [12 June 2022 15:27 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/6 "2022-06-12T15:27:36Z")

</div>

Ok I don‘t understand as well, so I can’t help you. Power should be 331 instead of -226 etc.

---

<div class="post-metadata">

**Author:** ![SeRiusRod](https://avatars.discourse-cdn.com/v4/letter/s/278dde/32.png) [@SeRiusRod](https://discourse.nodered.org/u/SeRiusRod)\
**Post date:** [12 June 2022 15:33 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/7 "2022-06-12T15:33:19Z")

</div>

Apparently the change node (I don't know if something else) input stuck at around 10h of this morning (It's 17:30h). It was receiving new messages but processing the old one. Or that "variable" became readonly.  
I'm just surprised because I never thought that was possible. I noticed because my home battery was getting overcharged. Ok, that's not possible because the charger limit it's still there, but I found very dangerous if something like this can happen.

---

<div class="post-metadata">

**Author:** ![mickym2](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/mickym2/32/36128_2.png) [@mickym2](https://discourse.nodered.org/u/mickym2)\
**Post date:** [12 June 2022 15:37 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/8 "2022-06-12T15:37:07Z")

</div>

This is why I hate function nodes. May be the function node sends more than one msg. The function node is the only one which would save a value within a context. The change node, with the code you posted has no context. In my opinion the output of your function node does not match the out put of the change node can only, that the function node sends additional messages.

---

<div class="post-metadata">

**Author:** ![Buckskin](https://avatars.discourse-cdn.com/v4/letter/b/b9e5f3/32.png) [@Buckskin](https://discourse.nodered.org/u/Buckskin)\
**Post date:** [12 June 2022 20:18 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/9 "2022-06-12T20:18:44Z")

</div>

Try setting (say) `msg.old` to `ms.payload` in the change node before changing `msg.payload`, this would show the before & after versions of `msg.payload` at the input to check mickym2's thought of more than one output from function node

---

<div class="post-metadata">

**Author:** ![SeRiusRod](https://avatars.discourse-cdn.com/v4/letter/s/278dde/32.png) [@SeRiusRod](https://discourse.nodered.org/u/SeRiusRod)\
**Post date:** [13 June 2022 09:28 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/10 "2022-06-13T09:28:39Z")

</div>

Oh!!! C-mon!! 🤦🏻‍♂️

 ![imagen](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/d/6d03c23170b098f3422b5f0a43c893aa18c515c4.png)

I'm so sorry. I'm so embarrassed.

---

<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:** [12 August 2022 09:28 UTC](https://discourse.nodered.org/t/where-change-node-gets-this-data/63823/11 "2022-08-12T09:28:50Z")

</div>

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