Immersion element size

[GUMPY]

Sonoff is what I use both in the caravan and at home. Has an app eWeLink handles 20amps and as a bonus records your power use.

 

SONOFF POW Elite 20A Smart Power Meter Switch, WiFi Wireless Outlet with Power and Energy Monitoring, Control Lights and Appliances from Phone, Manage Energy for DIY Smart Home,Works with Alexa https://amzn.eu/d/2v9l1sX

 

 

I went for the Sonoff to monitor the caravan power usage on metered sites to make sure I wasn't being ripped.

Once I had found out it has programmable on/off used it on the immersion at home.

I tried one with a temperature probe but fell down trying to get the programming right 🤔

[jonathanA]

I use a lot of the sonoff wi-fi switches at home, but they are limited to 10A per channel so didn't suggest them for this immersion heater at 3KW.  I'd be a bit careful using them at 10A TBH.  although they could be used to switch a more powerful relay/contactor easily enough. 

 

That version looks really quite good Gumpy.  The ewelink app is pretty good for chinese shite and you can get it to work with the likes of alexa. I think its limited to 4 on and 4 off functions per switch/channel.  I have one that controls my garage door  (alexa open garage door)* and also has an RF remote control 

 

one like this (which can also be powered by 12v Dc)

https://www.ebay.co.uk/itm/353180697331?hash=item523b35c2f3:g:7wkAAOSwyaNfQNJG&amdata=enc%3AAQAIAAAA4HGpp5ND7kUfsD6diaa%2FpMdTkHXRgM48s35RRGumYCykCAfGGvfHYmyB6lZPIf4e7lH8HgnPnl7HTlIWVYbsfvoeLR9ABcm4qAXCNSnnuAjymRN3vkwBcPpbsT7Y2%2BoOg2v7QkhkEP8OqdYX0H8yaRRFO24dJwus4DBxw0mhT8a%2BPbi3lbvPg%2FmPbs82pgonEfoPLWOuiJA8CVTlFHRT9tVHW%2BkuGQZq3Njew3f8zkoBJD6QgsfqQzX9iL2vfkX90QX3nZIjeujoLhU227Kte0BtLrTgDlYL2KMAYg5aNnSL|tkp%3ABk9SR7yD6pbsYg

 

* keep saying I'm going to change it to 'Open sesame' 🙂

[GUMPY]

2 hours ago, jonathanA said:

use a lot of the sonoff wi-fi switches at home, but they are limited to 10A per channel so didn't suggest them for this immersion heater at 3KW.  I'd be a bit careful using them at 10A TBH.  although they could be used to switch a more powerful relay/contactor easily enough. 

Hence I posted the 20amp one.

There is a 16amp one as well but there is  hardly any difference in price 🤔

I've got 3 on and 3off programmed into my immersion one.

[rusty69]

Are either of the devices above suitable for accurate measurement of incoming mains shore power?

 

One comment suggests no earth connection and limited cable size acceptance. 

 

I'm looking for a device to measure and log incoming mains power usage. 

[TheBiscuits]

On 25/10/2023 at 12:05, jonathanA said:

* keep saying I'm going to change it to 'Open sesame' 🙂

 

"To the Bat Cave!" has more style points 😁

[GUMPY]

41 minutes ago, rusty69 said:

Are either of the devices above suitable for accurate measurement of incoming mains shore power?

 

One comment suggests no earth connection and limited cable size acceptance. 

 

I'm looking for a device to measure and log incoming mains power usage. 

The 20amp one I posted HERE is fine for 16amp shore power, I use one to log the caravan power usage.

Yes there is no earth terminal on it, RCBO don't have earth terminals either🤔

Mine are fed with 2.5 cable which is fine for 16amp and fitted easily.

[rusty69]

Just now, GUMPY said:

The 20amp one I posted HERE is fine for 16amp shore power, I use one to log the caravan power usage.

Yes there is no earth terminal on it, RCBO don't have earth terminals either🤔

Mine are fed with 2.5 cable which is fine for 16amp and fitted easily.

Cheers. I just started a fresh topic to see what else is out there.

[GUMPY]

With a WiFi connection and  the eWELink  app you can read the data from anywhere

[nicknorman]

Do these devices retain usage information over a power cut? I have a cheapo plug in power meter but if you switch the power off, it loses its memory. So it’s ok for instantaneous power drain but not good for long term power usage.

[GUMPY]

41 minutes ago, nicknorman said:

Do these devices retain usage information over a power cut? I have a cheapo plug in power meter but if you switch the power off, it loses its memory. So it’s ok for instantaneous power drain but not good for long term power usage.

Yes provided it has power you can download 6 months usage from the Sonoff.

It exports in a .csv file, hourly for the whole six month period

Here is an edited snapshot of the data I have removed all the 0 readings 

 

 

data.pdf

Edited November 8, 2023 by GUMPY

[jonathanA]

7 hours ago, GUMPY said:

The 20amp one I posted HERE is fine for 16amp shore power, I use one to log the caravan power usage.

Yes there is no earth terminal on it, RCBO don't have earth terminals either🤔

Mine are fed with 2.5 cable which is fine for 16amp and fitted easily.

Actually most Uk RCBO's Have a 'Functional Earth' wire usually cream or white.  I'm not entirely sure why, something to do with 'reference to Earth' or losing the neutral connection, but have 'em they do.   I suspect you mean there is no provision for an Earth terminal on the sonoff devices. none of them do in my experience, your expected to provide the Earth/CPC connections if required as most of them need putting in some sort of enclosure really. 

[GUMPY]

38 minutes ago, jonathanA said:

Actually most Uk RCBO's Have a 'Functional Earth' wire usually cream or white.  I'm not entirely sure why, something to do with 'reference to Earth' or losing the neutral connection, but have 'em they do.   I suspect you mean there is no provision for an Earth terminal on the sonoff devices. none of them do in my experience, your expected to provide the Earth/CPC connections if required as most of them need putting in some sort of enclosure really. 

Believe me I have fitted thousands* of RCBO and I have never fitted one with an earth wire. Having said that some single module RCBO do as did the old ELCB.

The Sonoff device is designed to fit an enclosure but it's a bit shallow for UK enclosures unless you don't need to see the display which in practice you don't.

 

 

 

*Part of my working life was spent designing and building portable power distribution and each one was fitted with  78 or so RCBO 😉

[jonathanA]

3 hours ago, GUMPY said:

Having said that some single module RCBO do as did the old ELCB.

I should have said single module RCBO. In the context of the thread I had assumed that.