# Send Message Once

**URL:** <https://discourse.nodered.org/t/send-message-once/61477>\
**Category:** General\
**Created:** [19 April 2022 07:49 UTC](https://discourse.nodered.org/t/send-message-once/61477 "2022-04-19T07:49:40Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![mynoderocks](https://avatars.discourse-cdn.com/v4/letter/m/e274bd/32.png) [@mynoderocks](https://discourse.nodered.org/u/mynoderocks)\
**Post date:** [19 April 2022 07:49 UTC](https://discourse.nodered.org/t/send-message-once/61477/1 "2022-04-19T07:49:40Z")

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Hi all,

I am sure this is such a simple thing I am almost to embarrassed to ask. I have a simple flow, reads a value from MQTT (Grid voltage), checks if the value is in range using a switch node. If the value is =\< it sends a notification using PushSafer and Pushover notification service.

This works well, what I didnt factor for is using the switch node while the value is =\< the value I set it constantly sends the message. So during a outage I keep getting the messages.

The intent is for it to only notify me once and not constantly.

My question(s):

1. Did I use the wrong node (Switch node)
2. What do you recommend I use - the requirement is to only send me the message ONCE as the voltage drops below =\< value.

Thank you as usual!

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<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [19 April 2022 08:10 UTC](https://discourse.nodered.org/t/send-message-once/61477/2 "2022-04-19T08:10:02Z")

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You can use the RBE (filter node) to inhibit

e.g, something like this...  
 ![chrome_TadPBhacou](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/b/7bc1fbc122a57f9a05c6555812ede94a4e4f78b9.gif)

Demo flow (use `CTRL-I` to import)

```auto
[{"id":"3b79ef6fd5d51486","type":"inject","z":"7eecf5f1d763605a","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"1","payloadType":"num","x":352,"y":592,"wires":[["c9e1ac81b650e7ff"]]},{"id":"c9e1ac81b650e7ff","type":"switch","z":"7eecf5f1d763605a","name":"Less than 8 ?","property":"payload","propertyType":"msg","rules":[{"t":"lt","v":"8","vt":"num"},{"t":"else"}],"checkall":"true","repair":false,"outputs":2,"x":574,"y":640,"wires":[["1520ddd85115b2c0","a99855f1540228b7"],["35eb622363138bed","6c9a281f1d50b7ea"]]},{"id":"7aef8b8ccb2e899a","type":"inject","z":"7eecf5f1d763605a","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"5","payloadType":"num","x":350,"y":656,"wires":[["c9e1ac81b650e7ff"]]},{"id":"b64347d09d559c8c","type":"inject","z":"7eecf5f1d763605a","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"10","payloadType":"num","x":350,"y":720,"wires":[["c9e1ac81b650e7ff"]]},{"id":"1520ddd85115b2c0","type":"debug","z":"7eecf5f1d763605a","name":"","active":true,"tosidebar":false,"console":false,"tostatus":true,"complete":"payload","targetType":"msg","statusVal":"payload","statusType":"auto","x":762,"y":576,"wires":[]},{"id":"35eb622363138bed","type":"debug","z":"7eecf5f1d763605a","name":"","active":true,"tosidebar":false,"console":false,"tostatus":true,"complete":"payload","targetType":"msg","statusVal":"payload","statusType":"auto","x":778,"y":720,"wires":[]},{"id":"a99855f1540228b7","type":"change","z":"7eecf5f1d763605a","name":"WARNING. Value is below 8","rules":[{"t":"set","p":"payload_original","pt":"msg","to":"payload","tot":"msg"},{"t":"set","p":"payload","pt":"msg","to":"WARNING. Value is below 8","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":824,"y":624,"wires":[["f7c2fa40d22983da"]]},{"id":"6c9a281f1d50b7ea","type":"change","z":"7eecf5f1d763605a","name":"Normal (Above 8)","rules":[{"t":"set","p":"payload","pt":"msg","to":"Normal (Above 8)","tot":"str"},{"t":"set","p":"payload_original","pt":"msg","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":794,"y":656,"wires":[["f7c2fa40d22983da"]]},{"id":"f7c2fa40d22983da","type":"rbe","z":"7eecf5f1d763605a","name":"","func":"rbe","gap":"","start":"","inout":"out","septopics":true,"property":"payload","topi":"topic","x":1040,"y":640,"wires":[["d080866a75cdc7d8"]]},{"id":"d080866a75cdc7d8","type":"debug","z":"7eecf5f1d763605a","name":"","active":true,"tosidebar":true,"console":false,"tostatus":true,"complete":"payload","targetType":"msg","statusVal":"payload","statusType":"msg","x":1074,"y":688,"wires":[]}]

```

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<div class="post-metadata">

**Author:** ![mynoderocks](https://avatars.discourse-cdn.com/v4/letter/m/e274bd/32.png) [@mynoderocks](https://discourse.nodered.org/u/mynoderocks)\
**Post date:** [19 April 2022 09:56 UTC](https://discourse.nodered.org/t/send-message-once/61477/3 "2022-04-19T09:56:13Z")

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Thank you! Let me try that.

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<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:** [18 June 2022 09:56 UTC](https://discourse.nodered.org/t/send-message-once/61477/4 "2022-06-18T09:56:14Z")

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