# Urgent electronic problem (drive pump with 2 switches)

**URL:** <https://discourse.nodered.org/t/urgent-electronic-problem-drive-pump-with-2-switches/84221>\
**Category:** Hardware\
**Created:** [2 January 2024 20:02 UTC](https://discourse.nodered.org/t/urgent-electronic-problem-drive-pump-with-2-switches/84221 "2024-01-02T20:02:39Z")\
**Posts on this page:** 1\
**Showing post:** 27

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**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 January 2024 20:42 UTC](https://discourse.nodered.org/t/urgent-electronic-problem-drive-pump-with-2-switches/84221/27 "2024-01-06T20:42:46Z")

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> [@Trying\_to\_learn](#):
>
> I really think you got the NC and NO labels on the High and Low relays the wrong way around.

Yes, I noticed that later, and thought of a better solution.  
What I would do is reverse the float logic by using a resistor between +5v and the float, so that if the float contacts are open, the resistor ensures that the output is +5v.  
However, if the float contacts were closed, it would take the output to 0v.  
I would do it that way because, if the circuit was as it was previously, the 2 input relays would be energised all of the time, and only de-energised when the water level is high, which is not good practice (and a waste of energy).

![float](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/e/4e0c8a2299e6c39c06b93279c9e0b56223a9013b.jpeg)

I've not amended the circuit (as I don't know if Bart is interested or not), but well spotted @Trying_to_learn 👍

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