This page covers frequently asked questions about our wireless energy monitors. If you can’t find what you’re looking for, please submit a question at the bottom of this page.

Do they work with 3 phase power?


  • EW4008 and EW4009 – to measure three-phase power you need a total of three sensor clamps. The monitors ship with one sensor clamp per transmitter. You can buy two extra clamps (‘3 Phase Kit’) on the sale page.
  • EW4500 – this monitor has one LED sensor. It will report the usage from one smart or digital electricity meter (whether it’s single or three phase meter). If you have multiple digital meters, this product can only be attached to one of them.

Is the display screen portable?


  • EW4008 and EW4009 – these monitors can be mains powered (plugged in at one location) or run off the supplied batteries (portable). Please Note: battery power will only last for a few days. Remove the batteries when running off mains power, otherwise they will go flat and the screen will go blank.
  • EW4500 – this monitor is fully battery powered (and battery life is up to 5 years) – no mains plug required.

Can I use the energy monitor to check individual appliance usage?

Yes, to some extent. You do this by observing the difference in consumption when the appliance is turned on and off. The screen updates every 6 seconds (EW4008 and EW4009) or 30 seconds (EW4500).

To monitor individual appliance consumption in detail we recommend using the plug-in Power Meter or Power Mate Lite.

Can I download the data?

EW4008 / EW4009 – Yes. The products include a USB data cable. To download the driver and software for the monitors please refer to these pages (not compatible with Windows 8):

EW4500 – No data download available.

What data is available?

The EW4008 and EW4009 store 40 days of kWh/day and two years of kWh/month on board the monitor. You can extract more detailed data (minute-to-minute) if you connect your computer to the energy monitor and leave it connected with the software running.

Some customers have gone an extra step and then linked this data to on-line programs like PV Bean Counter. The chart below is from an installation of an EW4009 Solar Energy Monitor. It shows household consumption (red line) and solar PV production (green line) although the installation in this particular case does combine solar and usage during daylight hours (see installation guide below to avoid this).

PV Bean Counter EW4009 Chart

Can I enter three time-of-use tariffs from my smart meter?

Yes. These monitors can have three tariffs programmed into them (see manual for details).

Bear in mind that no energy monitor on the market can account for the true complexity of a three tariff system. This is because these tariffs change depending on what time it is, the day of the week and whether it is a public holiday (i.e. the monitor would need a complete calendar in it).

How far will the transmitter signal travel?

EW4500 – Up to 80 metres.

EW4008/ EW4009 – We have tested the signal to about 30 metres. It has been designed to travel through metal meter boxes and walls to that it can easily reach inside your home.

If necessary, extending the range further may be as simple as removing the cover of the transmitter and making the red antenna wire external to the plastic housing (see below). Here’s a blog post from someone who increased the range of a similar energy monitor product.

Inside Transmitter of Watts Clever Wireless Enegry Monitor

My meter box is over 30 metres away, can I still use the EW4008/9 monitor?

Yes. You should be able to clamp over the incoming supply cable before it gets split off into individual circuits at your household switchboard. We recommend using an electrician for this.

What size are the sensor clamps?

EW4008 & EW4009 – The internal diameter of the sensor clamp is 10mm (black clamp).

We also have some EW4008 units with 25mm (red clamp) available. Please contact us if you require this larger size.

Can I buy additional transmitters to monitor multiple circuits?

For example: one Clamp/Transmitter unit on the Hot Water Service circuit and another Clamp/Transmitter unit on another circuit such as the air conditioner?

Yes. The EW4008 can accept data in this way for up to 15 separate channels. The EW4009 can do the same for up to 5 channels. Please Note: Only the EW4008 can have all additional channels of data accessed via its software. The EW4009 software only accesses the main channels ‘Solar’ and ‘House.’

To order additional transmitter units please contact us by phone or email as you cannot buy individual additional transmitters directly off the website.

How do I install the EW4009 solar monitor?

An electrician will be able to help you clamp the sensor correctly. This is a simplified diagram of how it works:

Wireless Solar Energy Monitor Graphic

To successfully use this monitor you will need to be able to completely isolate your ‘household consumption’ from ‘solar production’ at your meter board. This is an example of how the unit can be installed:

  1. The “HOUSE” sensor/transmitter should be installed on the consumption only side of the main power switch at your meter board. If this can be done, it will only pick up your consumption – it doesn’t matter whether that consumption is being supplied by the solar panels or the grid.
  2. Next, the “SOLAR” sensor/transmitter is installed on the AC ‘output’ side of the inverter. It will measure solar PV production.
  3. Finally, the display screen calculates a NET value of the above readings and will show you the approximate amount of power being exported to or imported from the grid.

EW4009 Wiring Diagram - Solar Energy Monitor

Can I monitor solar power production from 2 inverters?

The EW4009 solar monitor only allows for one ‘channel’ or transmitter for solar data. However, it this channel allows for 3 Phase solar so you can purchase a ‘3 Phase Kit’ if you have more that one power cable carrying solar power at the board.

My EW4009 solar energy monitor is reading ~50 watts over night. What is this?

Your solar inverter will draw a small amount of power over night in standby mode. Unfortunately, what happens with these monitors is they pick up this current as production (because they can’t sense direction of current flow) and report the wattage too high. They measure VA’s but report watts.

This is the nature of CT current sensor clamps and how they work (ie. you would have a similar problem with any wireless energy monitor of this sort).

Can I use the EW4008 or EW4500 to monitor my solar to avoid the complexity of the EW4009 as explained above?

Yes. It all depends what you want to measure.

EW4008 – You can use this unit if you simply want to track solar production OR household consumption (as opposed to tracking both of these with the EW4009).

EW4500 – This unit will report back exactly what the smart/digital meter reports via the flashing LED on the front of the meter. In our experience this LED will stop flashing when solar power production exceeds household consumption.

In other words, it will report net household consumption. For example, if during the day your solar is producing 1kW and your house is using 2.5kW, the energy monitor will show a net consumption of 1.5kW. For this reason the EW4500 can often be a simple (install yourself) yet effective alternative to the EW4009.

Will I need an electrician to install the EW4500 smart monitor?

No, all you need to do is mount the LED sensor on the front of your smart or digital meter inside your meter box. Adhesive stickers are included in the kit for this purpose. Here are some example installation photos:

EW4030 installation examples

Will the EW4500 work with my solar meter?

Yes. Please see the explanation two questions above.

What does the bar chart and “0, -1, -2, -3, -4″ mean on the display EW4500 screen?

The EW4500 allows you to scroll through recent cost and consumption history on the screen.

The time periods available are Hour, Day, Week, and Month. When ‘Hour’ is selected and the square brackets are around the 0, data will show for the current hour’s energy consumption. [ -1 ] means last hour. [-2] means two hours ago, and so on.

The bar chart underneath these numbers shows the trend in consumption over the time period selected.

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