Alternative for power control

[Admiral Toad]

My mad sparky mate directed me to this

I have ordered one and will report back

Using one of these does not rely on a heat sink and resistors ie burnig up excess power as heat, but electronically switches off the power in milliseconds to lower the output so only uses the wattage you want to use therefore no neglidgle power wasteage

It's a it more expensive than some kit I've seen but worth a try

Watch this space

AT

http://uk.rs-online.com/web/p/power-mis ... 957&releva

[Capt-Cudellez]

That's a phase angle controller - I ran with one of those on my T500 worked really well. The connector pulls out at the bottom, if you accidentally do that while energised, then it can burn it out - which is what I did.

The whole casing is a heat sink, that the tiac is attached to - it will get hot.
this is what it looks like inside - click to enlarge

[Admiral Toad]

Have you ever considered going on mastermind mate x

[Admiral Toad]

Well I got this rigged up
Bit disappointed when I realised only 3 settings but apparently multiple variable ones are rather expensive
Seems to be producing about 50%,75% and 95% power on the 3 setting which hopefully should work
The kit is exactly as the good captain described so wondering how hot it will get cap'n ?
Should I make up a metal bracket to act as a heat sink ?

AT

[Admiral Toad]

Following on from last post it doesn't seem to be getting too warm but may just sandwich a bit of thin plate in where ot fixes on,and put some vent holes in the box

AT

[YHB]

Don't understand where the three settings come in? - The data sheet states "The regulator gives a fully adjustable output from zero to maximum voltage"

Are you sure they have sent you the right bit of kit?

[Admiral Toad]

Yes I took it in to my local RS components when I was getting some gear and had a chat with the very knowledgeable lads there.
There are better ones but you are in the hundreds
If CC used to use them I'm guessing it will do, it certainly is more efficient ie draws less power rather than using a pot

AT

[Capt-Cudellez]

Ah - that sounds to be a different model, mine was just a pot no switching settings.

[YHB]

Admiral,

There are two models hence my confusion, and from what I can see

Model (Captain C's controller) 214-3963 is variable from 0-240v and costs £46.98

Model (Your Controller) 214-3957 has three preset fittings and costs £47.40

I believe that the T500 has a 2000 Watt heater in which case the three settings are
1)
173v which will give you 1040 watts
2)
193v which will give you 1293 watts
3)
The third setting is just the same as plugging the T500 into the wall socket.

You may want to check it out.

[Admiral Toad]

Thanks Brian I think you've got a point there
I feel another visit to RS is in order

AT

[Admiral Toad]

The nice folk at RS swapped it over, hadn't realised they did a variable one
I'm getting a voltmeter too to see what works at what setting
Boys and toys

[YHB]

Admiral,

I am glad that you go things sorted, I am sure that you will find the variable controller a lot more useful.

When you get your voltmeter you will be able to see the voltage going up and down, what is perhaps more useful is knowing the "wattage" that the device is putting out because wattage is proportional to heat, so if you half the watts you half the heat.

This is a little complicated as there is a square root somewhere in the formula, for example if you half the volts you only get one quarter of the watts, ie if you get 2000w at 240 volts turning the voltage to 120 will only get a quarter of the heat.

The attached spread sheet converts volts to watts for any size of heater in any voltage, you may find it usefull, there again you may not.

Element Power Calculator rev 1.zip

(5.36 KiB) Downloaded 193 times

[Admiral Toad]

YHB

Yes I remember something like that from A level physics a long long time ago !
Well I've had it running tonight and it's just the donkeys whatsit very controllable and runs quite cool.I've found a nice small louvre vent on e bay so once the voltmeter is fitted as well that will complete a nice little controller box.
What I've got as well is a power meter on the mains feed, the type you can set up to see how much electricity you are buying, but more usefully has a kilowatt readout to 2 decimal places so when I've got a quiet morning with no other systems running I'll be experimenting to find wattage/voltage/control position etc
I know it costs a few quid but at least I'm using less juice when it's turned down
Thanks again Brian for spotting the better version

[Admiral Toad]

Fiddled around with the controller tonight but did run on full power after that

My approx findings for power output against voltage were
230v gave 1800w
200v gave. 1500w
175v gave 1150w
150v gave 950w
125v gave. 800w
100v gave 550w


The controller itself did get quite warm probably be ok but going to put a wee cooler fan in just to be on the safe side (£1.85 off eBay !) powered with a spare 12v psu I've got

Most pleased though