SD element controller with fan and LED switch additions

[AdelaideJon]

https://imgur.com/a/pdYhepZ" onclick="window.open(this.href);return false;" rel="nofollow

Hi All,

I bought a SD element controller kit (large). I am adding in a 240volt AC fan(polarity doesn't matter?) and a three pronged 240volt LED switch (positive in, positive out, negative). I have put the fan in as shown in the diagram. Is this ok? I am worried that the switch will be a short circuit, but this is how i was told it is to be wired up at JarCar.
Would it be better to put it in after the voltage regulator?

Cheers,

p.s. i have not turned it on yet and i will indeed get a sparky to check it before i turn it on.

[fizzix]

That's correct. No polarity on 240vac. And according to the notes, that switch has an LED on it to indicate POWER ON.
Still have it checked out though as it's easy to mis-wire those 3 terminal indicator switches if you're not use to them.
I've notated the "missing" LED (and assume there's internal circuitry to make it 240v compliant).

Please be safe and verify in person with someone in the know!

[Yummyrum]

https://imgur.com/a/pdYhepZ

Hi All,

I bought a SD element controller kit (large). I am adding in a 240volt AC fan(polarity doesn't matter?) and a three pronged 240volt LED switch (positive in, positive out, negative). I have put the fan in as shown in the diagram. Is this ok? I am worried that the switch will be a short circuit, but this is how i was told it is to be wired up at JarCar.
Would it be better to put it in after the voltage regulator?

Cheers,

p.s. i have not turned it on yet and i will indeed get a sparky to check it before i turn it on.

Hi AdelaideJon.
I'm assuming you're an Aussie and that JarCay is JayCar and having looked several times through their latest catalog , the only illuminated switch capable of handing an element is the 15 amp one I have shown . It has a neon in it not an LED and yes it has a built in resistor .
you hook it up as I have shown . Note the two terminals on the left are closer together than the third .

If this isn't the switch then a pic might help

[OtisT]

The diagram looks fine to me, with regard to placement of fan and switch.

What size element are you running (amp draw) and what is the amperage rating on that switch? I have been unsuccessfully looking for a 30amp switch with a profile like the one in the previous post. I found some 30a relays that were expensive and more complex. I ended up using a 30 amp rated switch that has a profile that looks like a home light switch.

I built out a SD large controller kit and am happy with with it. I personally found that adding both an amp meter and a second pot (fine tuning) is well worth the extra effort/cost. With only one pot, fine tuning your power is much more difficult. A small turn can cause a big jump or a little jump in output. W/o the meter, hitting a predefined power setting would be a challenge with each new run. For me, this was only an issue at low power setting, when I was trying to fine tune the boiler for taking fore shots while pot stilling or tuning for a desired reflux ratio.

Otis

[OtisT]

Hi there. I want to correct something I said earlier regarding wiring. (I said it looked ok). It is OK, but you may want to consider moving the fan connection. If you connect the fan after the regulator (parallel to your element) the fan’s speed will change with your voltage adjustments. Otis

[Yummyrum]

Otis why would you want to vary the speed of the fan ?
Maximum dissipation in a controller is not at full power but at less that full powe when the triac is switching from 0 to peak of the mains cycle . This is where the controller generates the most heat and the fan needa to be running the hardest so it seems counter productive to run it at slower speed where it needs to work the hardest

At minimum controller settings it may not start and possibly burn out .

[OtisT]

Otis why would you want to vary the speed of the fan ?
Maximum dissipation in a controller is not at full power but at less that full powe when the triac is switching from 0 to peak of the mains cycle . This is where the controller generates the most heat and the fan needa to be running the hardest so it seems counter productive to run it at slower speed where it needs to work the hardest

At minimum controller settings it may not start and possibly burn out .

You are way smarter than me yummyrum. You asked Why? so Here is my logic, though it may be flawed and I may be replacing my fan when it burns out:

Fans=noise. Faster fans = more noise, slow fans = less noise. I don’t like noise. My controller does not seem to generate that much heat, so I figured why do I need to run the fan at a full tilt boogie when I’m not generating that much heat. It’s a 10kwatt controller with a 5500watt element. I had not noticed my controller generating more heat at low power levels than at high levels, but I will pay attention next run and look for this.

I had noticed the fan won’t start at very low power levels, but my lowest run setting so far, nursing fore shots on a pot still run, is enough to turn it slow so it’s not stalled.

Otis.

[AdelaideJon]

Sorry all,
I didn't realise i had responses.
Am i missing something in regards to uploading photos? I kept getting errors so i just hosted on Imgur.
YummyRum, you are 100% right and thank you for the drawing.As it is an illuminated switch then it didn't seem to have continuity through terminals 2 and 3. So the guy in the JayCar told me it did not matter which way terminals 1 and 2 were connected. THIS IS WRONG. It seems that terminals 2 and 3 only get continuity when it has 240 volts going through it? A lazy sparky friend looked at it and said that my connections were safe and turned it on. This tripped my circuit breaker on the socket(my fail safe), the breaker in the house and melted the switch.
I got a new switch (and i told the guy in Jaycar he was wrong... which he denied) wired it up as YummyRum said and it worked fine.
Either a dodgy switch or a dodgy JayCar employee (and a dodgy sparky?). Electricity is dangerous.

The fan placement turned out fine. It was a really expensive one from Jaycar and it is very quiet.

So close to being done. I just need some bolt on parts to arrive in the post for cooling and i'm good to go. I'll post some pics soon.

Thanks for everything,
Jon

[Yummyrum]

Pleased you got it sorted Jon . Hope the rest of the build goes plain sailing .

Re: pictures
Maximum resolution is 800 pixals either vertical or horizontal , so you have to resize . I just open the pic in photoshop , resize to 800 pix and resave . Then use the resaved file for uploading . Its a fairly common requirement on a lot of forums .

Otis , Thanks for your answer . I get the noise issue .that makes sense
And yes you are right that the heat generated is bugger all and barely requires a fan anyway ..... mind you in Aussie we have a few hot days now and then .