StillSmart

Can anyone tell me why this set up may suddenly be having issues? I've been using it fine for a few months then the controller burnt out (literally) so I just put it down to them being cheap & got some more, they came today & I wired it in as shown. Now this all seemed fine, got it warmed up & collected about a litre on a strip run when suddenly the controller loses its mind & goes full tilt max power? Even with the dial right down it won't respond so I turn it off, thats when I notice how hot it all is I can hardly hold it. I give it 5 to calm down, check connections etc then plug in to try again, now it doesn't want to hold a steady wattage it's always slowly climbing even with me knocking it back then it does it again before shutting off completely....any ideas?

There is a difference between resistive loads (lamps and heaters) and an inductive loads (motors).

Which load is this controller designed for?

I'm sure it said all of them to be honest Mash?

EDIT: Just checked the bay, definitely says use as thermostat for water heaters etc

Have you got the link?

Yup yup https://www.ebay.co.uk/itm/131818621739

Sorry for the delay been conferring with a mate about it.

That is the correct type of controller for the job and should be up to what you want it to do according to the blurb.

It is very well priced, so perhaps you could expect the odd failure. CPC would rush you about £50 for a controller.

Not really any help I guess?

I bought 3 because it got me a little discount so I'll try one of the others & see if it does the same, I might try dropping it into something a little simpler as well like an extension lead just to see what's going on. It was very strange, just kept climbing then gave up!
Thanks for taking the time to look through it, your input is always appreciated

What's CPC? I'll see what cash is left next pay day, might get the United Automation one that Anavrin uses. It's expensive but 5 years steady use is only £20 a year, I'm over that this year already!!

CPC is a UK mainly electronics supplier,been around for years and a trustworthy supplier.

My power controller recently threw a do-hickey,after a couple of years of use, sending power levels all over the place, I put it down to the SSR and replaced it.

Robert

Just my 2 penerth on this.
I would think that it is overheating because of the lack of airflow.
As it warms up the r c characteristics alter and it swtches earlier
On the sine wave giving more power and getting hotter so going into a runaway state.
Hope that makes sense.
H..

You could well be right there, I have chopped a spare into an old extension lead with no box or anything just to see & it seemed fine. I only gave it maybe 40 mins before someone rudely decided to visit whilst I was busy & had to switch off, as it happens that wash turned out to be vinegar anyway so it saved me some electricity if nothing else!
Every cloud & all that!

jet2ride wrote:Just my 2 penerth on this.
I would think that it is overheating because of the lack of airflow.
As it warms up the r c characteristics alter and it swtches earlier
On the sine wave giving more power and getting hotter so going into a runaway state.
Hope that makes sense.
H..

Bang on. ...and I am perhaps a little annoyed for not spotting it myself - I have a similar device that heats my domestic hot water and I KNOW that is fan asssited - I am a beta tester for the company and raised issued about that very subject.

Well spotted. Mystery solved!

Passing that amount of current they run warm to hot and DO need airflow
whether convection or fan assisted. They should NEVER be fitted in a sealed
plastic container.
They are mounted in a housing full of holes for a reason.

I run my 2kW straight from the mains to reach temp and then connect the controller.
Saves it getting too hot passing max current.

Good 'breakdown' video here for anyone interested in them.
https://www.youtube.com/watch?v=_4PwYm_7HKg&index=11&list=WL

Hope that helps a little.
H..

Interesting vid....building a controller can be a hit & miss affair at times. It's good to know we have a expert on board when we have any questions...

My own homebuilt controller is installed into a metal box,with holes,no fan.
In fact just as YHB did viewtopic.php?f=15&t=1001&p=7821&hilit=power+controller#p7791 minus the fans,but with heat transfer paste.

Robert.

Is http://www.ebay.co.uk/itm/AC-220V-4000W-SCR-Variable-Voltage-Regulator-Motor-Speed-Control-Controller-Fan-/192027019684 OK for our needs? I was attracted by the fan and the scale round the knob compared to similar and only fractionally cheaper.