Do NOT buy this model

[nickds1]

Copied from my post in General Chat regarding Automating workshop with Alexa.

May I give you a warning about the RF remote switches, I used to use these before Alexa came on the scene and have had a few instances where the controlled device would come on without me touching the remote. I used to work with radio devices for MOD years ago and I know that radio waves do some really strange things so I would never trust those RF remotes to control anything more than a light.

Modern RF remote controls use a coded transmission that should not trigger on random noise etc. The code from the remote is paired with the unit to be controlled.

However, I agree that most of these units, e.g. the Sonoffs, are not suitable for controlling inductive machinery , i.e. stuff with motors.

I use Sonoff RFR3s for all my workshop lighting, and they're great, especially if after working late on a rainy night I get back to the house (about 100mtrs away) before realising I've left the lights on... with the RFR3s I can control the workshop lights from my phone or via a remote switch.

Where this all goes a bit wrong is in the design of these cheap controllers. They're cheap for a reason - they've been "Muntzed", i.e. any part that's not absolutely necessary is removed.

Specifically, whilst the relay & the adverts say "10A", that means maybe 10A non-inductive load. These devices contain no snubbing across the relay contacts, which means that if you stick a decent inductive load on them, e.g. a 2KW extractor, the contacts will arc and in due course fail. either by welding themselves together or simply not turning on any more due to carbonisation.

Another grim bit of design in them is that the supposed 10A capacity is carried by PCB traces that have been built up a bit by lumping bits of solder not very evenly onto them. THIS IS NOT CAPABLE OF CONTINUOUSLY CARRYING 10A SAFELY! In practice, the PCB traces are likely to blow way before that, i.e. an uncontained fuse wire.

They are simply not designed for workshop equipment - if you want to remotely control inductive loads with one of these, use the RF switch to control a proper DIN-rail contactor and let the contactor safely do the heavy lifting which it is designed for.



Never in your wildest dreams should you put 10A, inductive or non-inductive, through these devices. Even the terminal block (screw connectors) are so small they're only rated for 5 or 6A.

 

[Hutzul]

I've used these (same make & model) in my house for 20+ years with no issues at all.
Sorry to hear about your problems with same

 

[nickds1]

EDIT: You (Hutzul) may have been replying to the OP rather than the previous post (you don't make it clear), in which case apologies, but my points below about inductive loads and all these types of devices still stand.

I've used these (same make & model) in my house for 20+ years with no issues at all.
Sorry to hear about your problems with same

Did I say anywhere that I had a problem with them?

I've used these (same make & model) in my house for 20+ years

Really? These units are all based on the ESP8266 (or its derivatives) SoC from Espressif Systems and that chip only became readily available in August 2014, so less than 8 years ago - the ESP8285 (essentially a bigger 8266) is used in some newer devices and that was first released in April 2016. The RFR3 also only got it's FCC & CE certifications in 2021, so a bit later than 2002...

I use several of them, as I stated, very successfully & safely for lighting control. What they are not safe for is in the control of inductive loads and anything approaching their stated capacity of 10A - 10A is only mentioned as that's the stated capacity of the relay itself (not the system) for non-inductive loads.

So, not safe for workshop control of motors. They may work, and if you are controlling inductive loads and it's worked for you so far, well done - I hope your luck holds.

However, there are serious design weaknesses which are immediately evident to any electronic or electrical process engineer that make these units potentially unsafe with at least three failure modes, two of which could result in fire or a machine that's difficult to turn off.

Just because you can get/have got away with something doesn't mean you should or that it's a good idea.

These units are very functional, but have design weaknesses that render them dangerous for certain use cases. If you want to control a decent load, use one of these to drive a contactor and snubbing or an ZCS SSR (Solid State Relay), i.e something that's designed to do that specific job safely.

 

[stuart little]

Copied from my post in General Chat regarding Automating workshop with Alexa.

May I give you a warning about the RF remote switches, I used to use these before Alexa came on the scene and have had a few instances where the controlled device would come on without me touching the remote. I used to work with radio devices for MOD years ago and I know that radio waves do some really strange things so I would never trust those RF remotes to control anything more than a light.

Brings back a memory of being at the top of Mt.Ventoux, in Provence, when for no reason my car alarm beeped & switched on. I guessed it had to do with radio waves from the military installation nearby, which you'ved now confirmed. Ta!

 

[Lard]

I’ve used the sonoff’s and remote controls with my extractor for years with no issues…..it, however, controlled by a contactor.

I’ve also got my consumer unit positioned by the door to the workshop so I’ve always had a habit of shutting off the whole unit as I leave.

Don’t go throwing out the baby until you’ve considered some SAFE work arounds.

 

[HamsterJam]

Brings back a memory of being at the top of Mt.Ventoux, in Provence, when for no reason my car alarm beeped & switched on. I guessed it had to do with radio waves from the military installation nearby, which you'ved now confirmed. Ta!

I am familiar with high power radio frequency (RF) energy and recall some years ago when remote control locking was becoming common place in family cars, there was one model in particular that was difficult to unlock or start when subjected to a modest RF field. More than once did we have to push one off site so it could be started.

 

[Sandyn]

Correct me if I misunderstand but this doesn’t look like like a safety issue with the device itself, rather the use the device is being put to.
i.e. the hazard the OP refers to arises from power being unexpectedly applied to devices for prolonged periods which in some cases causes them to overheat.

My guess is that in pursuit of cost reduction, immunity to false triggering has not been properly considered in the design.
As well as using a certain radio frequency or channel, the remote sends a signalling sequence to address the right socket and indicate whether it should turn on or off etc. The chips to do this are a standard commodity and will be bought in by the manufacturer.
My guess is that this socket either uses a very simple signalling sequence or a default sequence, maybe both. This will make it prone to interference from other devices or perhaps just radio noise.

I can see your point, but the device is sold as an wireless isolating switch. If this switches on at random, it is absolutely a safety issue. A user might have a radiant electric fire attached to it and expect the fire to stay off when switched off. They turn the switch off using the remote, move the fire out of the way. During the night, the switch randomly turns on, the electric fire is pointing at flammable material and sets the house on fire. So whilst the device itself is 'safe' it's function is not. Your comment does highlight some of the loopholes which exist. A good manufacturer would never sell a product with such a fault. There is a possibility that the device does have full safety/EMC certification, because safety testers may have difficulty finding this problem and EMC testing doesn't look at safety, so during testing, if the manufacturer is not looking for this problem, it would never be spotted. If I was designing or testing a device such as this, in EMC or safety. I would absolutely focus on false triggering.

 

[Lefley]

Interesting. How is it enforced?

Your insurance will not pay if your house burns down and any electrician would lose his license if he was the one that installed non approved lighting or appliances.

 

[Lefley]

There is a cheap solution to your problem


View attachment 130501

Nice. But all my leds have dimmer controls and also will change from warm light to daylight and in between. Also will come on from movement of sound when enter shop. All controlled from a remote. Right now I do operate them from a switch but any time I change parameters in lights I have to do it 6 times for the six lights.

 

[baldkev]

I turn off & unplug everything in my workshop after working in there....The only thing that's left powered up is the Alarm system and even that has a battery back up....

I know people who leave tool batteries on charge overnight.....They must be mad taking that sort of risk!

Someone locally left their makita charger in a customers garage over night.... the following morning the charger was a lump of melted plastic and the back of the door was a bit black! Luckily no major damage!

 

[Scruples]

Copied from my post in General Chat regarding Automating workshop with Alexa.

May I give you a warning about the RF remote switches, I used to use these before Alexa came on the scene and have had a few instances where the controlled device would come on without me touching the remote. I used to work with radio devices for MOD years ago and I know that radio waves do some really strange things so I would never trust those RF remotes to control anything more than a light.

You're right, I have the same remote controlled sockets and, just occasionally one will turn on. At first, I thought it was a fault so I complained to the supplier who sent me a new set, but the same thing happened.

It's cheap and, if used on circuits/appliances/tools that won't hurt from being switched on without warning then they are useful. I have four that control lighting in my lounge/diner and it's so much easier to hit the on/off remote than doing the rounds of the sockets twice a day. It comes down to choice, price and convenience in the end.
I did have my workshop vac on a remote socket, but I found that the remote was usually as inaccessible as the vac switch, and, if the vac came on in the night I would be wasting some significant power so I'm happier using the socket switch for that.

 

[Scruples]

Someone locally left their makita charger in a customers garage over night.... the following morning the charger was a lump of melted plastic and the back of the door was a bit black! Luckily no major damage!

I bought electronic countdown sockets which can be set for 15/30/60/120/240/480 mins for battery charging. They're about a tenner on Amazon and work well. They don't consume any power when off.

 

[Skydivermel]

I think it's best to turn off and unplug everything when you leave the workshop.

That's exactly what I do. The only thing I leave on is the oil filled radiator set on low.