# Options for SPDT pool pump switch?

**URL:** <https://community.smartthings.com/t/options-for-spdt-pool-pump-switch/220151>\
**Category:** Projects & Stories\
**Tags:** switch\
**Created:** [February 8, 2021, 2:42pm UTC](https://community.smartthings.com/t/options-for-spdt-pool-pump-switch/220151 "2021-02-08T14:42:11Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![crosjn](https://avatars.discourse-cdn.com/v4/letter/c/f4b2a3/32.png) [@crosjn](https://community.smartthings.com/u/crosjn)\
**Post date:** [February 8, 2021, 2:42pm UTC](https://community.smartthings.com/t/options-for-spdt-pool-pump-switch/220151/1 "2021-02-08T14:42:11Z")

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Alright, I’m trying to bring automation to my pool pump but it’s a little trickier than I’ve seen others discuss. I have the standard 3-wire setup (two 120v mains and a ground) running through the tried and true Intermatic timer. The timer is just on/off. One 120v wire runs to the motor. The second 120v though runs through a SPDT switch that acts as the high/low selector switch (For those unaware or if I’m unaware, I mean this switch cannot be off, it has one input and two outputs with one output always active and both cannot be active at the same time.) Is there a failsafe way to recreate this circuit?

I have no idea what happens if you energize hi&low simultaneously and would like to make sure it never happens. (I used to think “what are the odds?” until I created a race condition in a ST lighting automation that didn’t trigger for years - until we went on vacation and a neighbor triggered it. A couple of hundred dollars in lights died that holiday after they strobed non stop for somewhere over 48hrs.) 🙂

Thanks in advance and if this has been covered, I do apologize. It wasn’t for a lack of searching.