26 minutes ago, Stalky said:

 

If so, maybe there is a way to improve the connection so that it does not overheat from arcing or poor contact.

Comments?

From Stalky (New Sonoff user)

@Stalky  I agree it is better to use a relay . Multi strand cable does not connect well on the Pow 2 Sonoff . connections . Single wire makes a better connection .

Hi Riaanh,

I'm particularly wanting the consumption feature.

considering changing the geyser element to a 2000w to lower the amps to 9A.

Can one modify the connectors to be better contacts?

Has anyone had the actual little 16A relay on the POW R2 circuit board melt?

 

A bit late to this party but thought I'd give my input as I looked at this some time ago......

I wanted to control my geysers with a Sonoff but when you look at the wire terminals and AC tracks there is no ways this is a good idea regardless the AMP rating, I bought 2 solid state relays which I was going to use in conjunction with the Sonoff's but when these were both faulty on supply I called it a day, had they been functional I probably would have gone ahead with it but to me the stars were not aligning in my favor. 

Don't get me wrong, the Sonoff products are great and I use them quite extensively but I personally steer clear of using them in high current scenarios.

If you're wanting to control a geyser I think its good / safe practice to get the Sonoff to switch an external relay which handles the heavy current and if you're wanting to measure power draw / consumption etc... probably makes sense to rather use CT clamps, there are easy enough and cheap enough options using something like a nodemcu board or similar.

PS, the highest amperage I have running through a Sonoff Pow R2 is my pool pump which runs typically at 1000w / 5A. I think I've had this installed for over a year with no issues to date, all my other applications are relatively low draw such as lights etc...

On 2020/01/30 at 11:48 AM, Stalky said:

Hi. All the photos seem to indicate that the burning involves the connectors for the wires, and not actually the relay on the POW R2 board itself.

Is this the case?

If so, maybe there is a way to improve the connection so that it does not overheat from arcing or poor contact.

I wonder if it is possible to solder the wires into the connectors in some way?

Maybe solder some wires to the underside of the board

1 hour ago, Pietpower said:

I wonder if it is possible to solder the wires into the connectors in some way?

Maybe solder some wires to the underside of the board

You could definitely do that but it's not going to change anything, push too many amps through the Sonoff and you'll burn it regardless, its dangerous using a Sonoff like this I really wouldn't recommend doing this there are better (safer) ways to control a geyser.

I use a 20A 1P DIN rail contactor that I imported from China (ages ago) in conjunction with Sonoff switches.  Sonoff switches contactor  - contactor switches pump, geyser etc. Contactor were bit noisy to begin with but now are quiet. Even though a Sonoff is rated at 16A you can see that the terminals are not designed for that sort of load. Unless you already have a relay I would go with a contactor they are a bit more robust and if you get a normal 3P contactor you can switch both live and neutral which I like.

9Amp through a 16Amp rated unit is surely within limits?  It is those bad connections that cause most of the problem.

Yes using a proper contactor is the correct way of doing it.  But then you can use the basic 10A Sonoff which is cheaper.

When you connect the Pow R2 to a contactor you lose all of it's features.  It can give you the kWh used by your 2kW geyser.
You can set power limits to cut out earlier if you don't want to get close to the 16A limit.

On 2020/01/07 at 7:14 AM, Quwatush Shams (Suly) said:

Sourced from Communica

Any diagram available on which pins to use on the relay for the sonoff and for the power to the geyser

"Any diagram available on which pins to use on the relay for the sonoff and for the power to the geyser"

I bought the same Asiaon 40A relay but can find a wiring diagram on what pins to connect to what. Can anyone help?

Here are the pins on the Asiaon 40A JQX-40F 1Z

Any advice on which pins to connect the sonoff, 240v and the Geyser to, would be much appreciated!

14 minutes ago, Goose99 said:

Any advice on which pins to connect the sonoff, 240v and the Geyser to, would be much appreciated!

The 2 small pins by your thumb go to sonoff

Cut live wire only going Geyser after isolator and connect as below

 

Edited July 15, 20206 yr by Quwatush Shams (Suly)

4 minutes ago, Quwatush Shams (Suly) said:

The 2 small pins by your thumb go to sonoff

Thank you!

This is the product spec of the relay so as per the wiring diagram on that page:

.... where do the L,N,E for the geyser and 240v go?

9 minutes ago, Goose99 said:

where do the L,N,E for the geyser and 240v go?

Only L and N from sonoff switch are used and as stated only 2 terminal on relay are used on L wire as shown above in pic everything else stays the same as it was

I got power for sonoff from before the isolator but honestly you can use any plug/light L and N thats close by to feed power 240v to sonoff

Essentially relay is to swtich on/off (geyser) and sonoff controls the on/off (on relay)

Hope that makes sense

Edited July 15, 20206 yr by Quwatush Shams (Suly)

Apologies, I posted my reply before you edited your initial post. But yes, this makes perfect sense! And thanks for the pictures, they're always worth a thousand works! Cheers

Below is some images of the connectors on the Sonoff switches.  The second Image is with a piece of solder wire.

I am still of the opinion that these burn out due to bad connections at the connectors and not the switch itself.

Only the live circuit actually goes through the circuit board.  Neutral is connected direct to neutral and bypasses the board.  The switch has a thin solder line from neutral to power the board.  Earth is the same and it does not seem to be connected to the electronics on the board at all.

What I think:
- You have to press the white tab when inserting the wire to get it in all the way to the back.
- The wire easily get stuck halfway into the connector.
- Solid strands/wire (twin&earth) easily fits but the cable does not bend easily and put a lot of strain on the connectors
-  I have used 2.5mm² stranded wire and soldered only the first mm so that the strands can expand a bit under spring compression.

Nice Piet! This is very cool to see - thanks for the effort!

Is this connector from one of your failed devices? Are those burn marks on the switch from the failed device?

3 hours ago, Goose99 said:

Nice Piet! This is very cool to see - thanks for the effort!

Is this connector from one of your failed devices? Are those burn marks on the switch from the failed device?

Yes this is a connector from a burnt device.  Did not do a proper job of connecting the neutral wire.

Actually the device is still functioning although calibration is out.  Removed the connectors and replaced with normal screw blocks.

Replaced this switch with a new one though.

Initially, I wanted to use the POW R2 just for the measurement. It would never do the switching, as I use a Geyserwise for that.

After playing with HomeAssistant though, I'm going to give it a go.

Based on what I've read here, I'll rather attempt the following:

• Use a Sonoff Basic, flashed with Tasmota
• Use the Geyserwise thermometer attachment as input to measure the temp
• Use something like this (https://www.netram.co.za/1128-30a-max-non-invasive-ac-current-sensor.html) connected through a voltage divider to another GPIO input (maybe the button, as this won't be needed anymore) to measure current
• Some 30A relay mentioned in the post so far to do the actual switching
• Schedule the on/off times and max temp with HomeAssistant

Should be a nice little project, as this would allow you to:

• Define a schedule via HomeAssistant
• Define a maximum water temperature
• Change the schedule of the heating based on other inputs, i.e. temperature outside, seasons, sunset/sunrise, number of people at home (through presence tracking)
• Remote control
• Report on the power draw

3 hours ago, Cello said:

• Use something like this (https://www.netram.co.za/1128-30a-max-non-invasive-ac-current-sensor.html) connected through a voltage divider to another GPIO input (maybe the button, as this won't be needed anymore) to measure current

I see that clamps around the wire and haqve a 3.5mm jack.  The Sonoff TH16 (temp) has a similar input. Wonder if you could reprogram it to work with this device.

On 2019/07/21 at 1:04 PM, MartinCoetzee said:

through a 2ndary relay to take the load.

 

Edited July 22, 20206 yr by flamegrilled

Hi, does anyone know where I can get 30A relays for 240VAC at the R30-R40 that everyone speaks of? Everywhere I look they only start at ±R210. This is for the Sonoff and relay config discussed on this thread.

On 2020/07/27 at 10:13 AM, Rian-II said:

Hi, does anyone know where I can get 30A relays for 240VAC at the R30-R40 that everyone speaks of? Everywhere I look they only start at ±R210. This is for the Sonoff and relay config discussed on this thread.

Nevermind, it turns out it's the difference between a relay that switches on 12V DC vs 220V AC. I already had the Sonoff Basic R3 (which requires AC input) and would like to put the Sonoff and Relay setup inside my DB Box (and make sure it is within regulations), hence I went with the 220V AC relay. It is much more expensive though.

This is the relay. Any advice on which pins to connect to? Will really appreciate the advice!

 

9 hours ago, Rian-II said:

Seeing that the relay switch with 220VAC you can easily test which wires to connect to make it switch by supplying it with 220V AC (wire it up to a house plug you can switch on/off). You will hear the "click" when it switch. Most likely it will be pins 3 & 4 that you need to power for it to switch. Else it will be the other 2 pins. 

14 hours ago, Louisvdw said:

Seeing that the relay switch with 220VAC you can easily test which wires to connect to make it switch by supplying it with 220V AC (wire it up to a house plug you can switch on/off). You will hear the "click" when it switch. Most likely it will be pins 3 & 4 that you need to power for it to switch. Else it will be the other 2 pins. 

Thanks @Louisvdw, that's a great idea. I also thought it could be pins 3 and 4 for the switch, considering pins a and b looks like it's at the coil.

Edited August 3, 20206 yr by Rian-II
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