# 3 Phase whole house, PV and heat pump monitoring required

**URL:** <https://community.openenergymonitor.org/t/3-phase-whole-house-pv-and-heat-pump-monitoring-required/2313>\
**Category:** Getting Started\
**Created:** [25 November 2016 17:54 UTC](https://community.openenergymonitor.org/t/3-phase-whole-house-pv-and-heat-pump-monitoring-required/2313 "2016-11-25T17:54:07Z")\
**Posts on this page:** 1\
**Showing post:** 2

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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:** [25 November 2016 19:30 UTC](https://community.openenergymonitor.org/t/3-phase-whole-house-pv-and-heat-pump-monitoring-required/2313/2 "2016-11-25T19:30:24Z")

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> [@Heteractis](#):
>
> I posted about this topic a few months back

[https://openenergymonitor.org/emon/node/12286](https://openenergymonitor.org/emon/node/12286)

> [@Heteractis](#):
>
> The house supply is running through a Polyphase Energy Meter 5219 which I believe has an optica/pulse output which could also be used but I am not sure if this is better/what it would replace from the EmonTx + clip on sensor?

The easy one first: The meter pulses will only give you consumption, you will get no pulses when you are exporting. So although by definition that meter is totally accurate, the pulse output is only half the story. The other point, which might not bother you, is you only know about consumption after the event when a pulse is generated. And of course, resolution is one pulse (1 Wh for your L+G meter).

> [@Heteractis](#):
>
> From what I have read, I would need 3 x EmonTx with 3 x 100A clip on current sensors for the consumer units but would I also need another 3 for the PV monitoring or could it all be done from the 3 x EmonTx’s?

If you had the 3 emonTx’s in the garage, where presumably you have your meter, Henley Blocks and the PV isolator, you could monitor both PV generation on each phase and the nett import/export on each phase. (The difference of course being consumption on each phase.)

But that won’t give you any details about individual circuits.

> [@Heteractis](#):
>
> Also, I have an ASHP which I would like to monitor.

It looks as if this will need its own emonTx (Can you confirm it has a single phase supply?) or, from what I know about it, this:

> [@Heteractis](#):
>
> the through-hole kit

Is this the [heatpump monitor](https://community.openenergymonitor.org/t/heatpump-monitor-update/999) that’s presently in development?

> [@Heteractis](#):
>
> I believe I would also need a single phase electricity meter on the heat pump supply (although I have a supply to an indoor unit and an outdoor unit seperately for my heat pump so I might need two…??),  
> …  
> Although could I just use an EmonTx with two clip on current sensors to measure each supply to the heat pump without the electricity meter being required?

Yes, the emonTx/Heatpump Monitor would surely be instead of, not as well as, another meter? The comment above about pulses applies here too.

If the indoor and outdoor units are on the same phase, and fed from roughly the same place, then a CT on each will give you the individual consumptions of the two units.

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_[View the full topic](https://community.openenergymonitor.org/t/3-phase-whole-house-pv-and-heat-pump-monitoring-required/2313)._