# 3 Phase Question

**URL:** <https://community.openenergymonitor.org/t/3-phase-question/4979>\
**Category:** Getting Started\
**Created:** [1 September 2017 11:21 UTC](https://community.openenergymonitor.org/t/3-phase-question/4979 "2017-09-01T11:21:49Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![johnbanks](https://community.openenergymonitor.org/letter_avatar_proxy/v4/letter/j/c6cbf5/32.png) [@johnbanks](https://community.openenergymonitor.org/u/johnbanks)\
**Post date:** [1 September 2017 11:21 UTC](https://community.openenergymonitor.org/t/3-phase-question/4979/1 "2017-09-01T11:21:49Z")

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I’m running an emonTx with 3 phase firmware to monitor an air source heat pump.  
emonTx has an AC adapter connected.  
Can I CT monitor just one phase of the input to the ASHP and multiply by 3 to get a reasonable idea of the total power consumed by the ASHP?  
Does the CT need to be on the same phase as the AC adapter?  
Thanks

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**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\
**Post date:** [1 September 2017 13:39 UTC](https://community.openenergymonitor.org/t/3-phase-question/4979/2 "2017-09-01T13:39:08Z")

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If your ASHP represents a balanced load, then yes, and you don’t need the 3-phase sketch in that case (but any other c.t’s that you use must be on the same phase, or you can have apparent power only).

> [@johnbanks](#):
>
> Does the CT need to be on the same phase as the AC adapter?

That is answered in the comments at the top of the sketch.