# How to seperate payload\_fields into two topic in 'MQTT IN' node

**URL:** <https://discourse.nodered.org/t/how-to-seperate-payload-fields-into-two-topic-in-mqtt-in-node/18211>\
**Category:** General\
**Created:** [21 November 2019 00:10 UTC](https://discourse.nodered.org/t/how-to-seperate-payload-fields-into-two-topic-in-mqtt-in-node/18211 "2019-11-21T00:10:35Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![molly](https://avatars.discourse-cdn.com/v4/letter/m/df788c/32.png) [@molly](https://discourse.nodered.org/u/molly)\
**Post date:** [21 November 2019 00:10 UTC](https://discourse.nodered.org/t/how-to-seperate-payload-fields-into-two-topic-in-mqtt-in-node/18211/1 "2019-11-21T00:10:35Z")

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I have already made two signals humidity and light shown in payload\_fields in debug message, **how can I seperate them into two independent value or two topics?** Because after the MQTT IN node, I need to display two signals in the chart which need the real value of the signals.  
Another one is I only have one topic now which is /devices//up of ttn, **how can I make this topic into /devices//up/humidity or /devices//up/light** , because now if I set the topic into /devices//up/humidity,there will be nothing shown in debug window.

 ![question](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/c/c3074001915697919c36350cad911498e1302b7f.jpeg)

Thanks so much!

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**Author:** ![bakman2](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bakman2/32/6207_2.png) [@bakman2](https://discourse.nodered.org/u/bakman2)\
**Post date:** [21 November 2019 06:48 UTC](https://discourse.nodered.org/t/how-to-seperate-payload-fields-into-two-topic-in-mqtt-in-node/18211/2 "2019-11-21T06:48:58Z")

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> [@molly](#):
>
> I need to display two signals in the chart which need the real value of the signals.

You can already use the data shown in the screenshot in a chart node by using a change node.  
mqtt-in -\> change node -\> chart node, in the change node use:

 ![32](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/e/ea62a78db662ec292f898a7726c690c9f6d6f0a5.jpeg)

add an additional change node and chart node for the light.

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**Author:** ![molly](https://avatars.discourse-cdn.com/v4/letter/m/df788c/32.png) [@molly](https://discourse.nodered.org/u/molly)\
**Post date:** [21 November 2019 22:45 UTC](https://discourse.nodered.org/t/how-to-seperate-payload-fields-into-two-topic-in-mqtt-in-node/18211/3 "2019-11-21T22:45:11Z")

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Thanks so much! It works!