DIY Power Controller

Lloyd

Tode you someone smart would chime in.
Its a gift I have really, predicting the future, it will rain tomorrow so bring your umbrella.
Unless its hot tomorrow with no rain and the umbrella protects you from the sun.
Bases covered either way.

Thanks Micki, I fully expect to pull you out now when answers are needed (and don't forget your umbrella - it could actually rain tomorrow).

Brewhaha

Thanks for the replies Punkin, Lloyd & Mickiboi I'm like you Lloyd don't know much about electronics at all may your first SSR Rest In Peace. That is exactly why I'm asking first and making sure I'm on the right track.

Its great that I can get information from experienced people on the forum. Mickiboi thanks for the info the reason I asked about a varistor was when doing research I came across a US Seller of kits and he mentioned that StillDragon didn't supply a varistor with there kit.

Which lead me to this forum to check it out. I have already purchased the StillDragon kit and have got some neat features to add to my Boiler controller thanks to cityshineboy I'm off to Bunnings for a plug and extension lead and Jaycar for a switch.

I found a voltage and wattage digital gauge, but it has no instructions but I'll put some pictures up and maybe someone can point me in the right direction for wiring it in eBay power meter

Cheers

Lloyd

Cool, tricking out a DIY, love it!
Don't keep us hanging, tell us everything - the good and the bad.

The DIY kit is kept simple on purpose but your ability to add features will benefit everyone when you share.

Philter

@Brewhaha I have a used few of those power meters on my controller, and am relatively happy with them.

I've burnt out the shunt resistor on one meter (running it at 4.5kW), and they won't give an accurate reading when using pwm, phase angle or burst fire controllers.

Yell out if you need some help with it :D

Brewhaha

Hi Philter, thanks for sharing the info with the meter and the offer for assistance. I have a 2200 watt element which I have since been told there is a lot of faults being reported and blow ups with them... if it gets replaced it will only be a 2400 watt low density element Its only a small hobby still but I want to control water cooling condenser flow rate and boil temperature.

I replied to Loyd that I didnt even know what the donut thing was I guess now its a shunt resistor and you now know the extent of my electronics knowledge :)) . The meter is on a slow boat from china so when it arrives I will certainly need assistance. Cheers

fadge

@Brewhaha said: Hi Philter, thanks for sharing the info with the meter and the offer for assistance. I have a 2200 watt element which I have since been told there is a lot of faults being reported and blow ups with them... if it gets replaced it will only be a 2400 watt low density element Its only a small hobby still but I want to control water cooling condenser flow rate and boil temperature.

I replied to Loyd that I didnt even know what the donut thing was I guess now its a shunt resistor and you now know the extent of my electronics knowledge :)) . The meter is on a slow boat from china so when it arrives I will certainly need assistance. Cheers

DISCLAIMER- Not an electrician, just a fellow hobbyist.

The doughnut thing is for current measurements, a live "hot" wire passes through it. Just one of the 2 wires that goes to the element.

Normally with these meters the voltage is 2 wires across the point that's measured, and the doughnut thing for current.

I'm not familiar with the one you have shown however, and some meters will not be able to accurately display due to the way the controller chops up the power in a way to control output.

I have a controller with a meter, displays both voltage and current, does not matter if really accurate, only that I can dial it in to the same spot on any run. It was a cheap ebay job. There is a video somewhere showing mine.

I'm in the top North Vic region if ever you need a hand.

fadge

olddog

All of the instruction enclosed in the meters I have used show the negative wire passing through the doughnut

Lloyd

The NEGATIVE WIRE? So that's where I went wrong.

Told you I was an electroidiot. But still you don't believe me.

Logic and electronics collide, yet again. RTFM, YMMV, WYSIWYG, FMIL (f*k me I'm lost).

Brewhaha

@olddog said: All of the instruction enclosed in the meters I have used show the negative wire passing through the doughnut

I asked the seller if instructions came with it, the reply was no instructions. The image with wiring came from a similar but not the same meter on eBay. By the time I get it I'm hoping I will have sourced the correct wiring info for the meter and will then be able to get help to install it correctly.
Thanks @fadge for your info I live in Northern Rivers N.S.W so if I get assistance from you it will more than likely be through the forum. Thanks for your reply also @olddog I appreciate all the input I'm getting from forum members it all helps
Cheers

Grudaire

The doughnut is a current transformer. It does the same thing as a shunt. Just pay close attention when wiring those Chinese monitors as they switch things around so if they have a wiring diagram online the part you receive may wire up differently. I have smoked a few trying to get things correct, they are cheap enough that the real hassle is waiting for another to arrive.

fadge

This link is the same type I have used, pics show simple 2 wires for voltage and the current loop. The voltage and current connections are on the output side, ie element side of your controller.

Blue LCD AC volt & amp combine 2 in 1 panel meter 300V 50A for 110V 220V 240V @ eBay

These are a basic unit but work ok for what we are doing, they are small enough to fit cases ok as well.

jonno

Your supposed to pass the active wire through the hole.

ozarks_irishman

Wired mine on the hot wire, works just fine that way....maybe I'll check it with another amp meter out of curiosity.

olddog

Won't matter much either way as its alternating current

Myles

Just so long as you only put 1 wire through the hole. ;)

Grudaire

@Myles said: Just so long as you only put 1 wire through the hole. ;)

What if it alternates between two wires?

Come on that's just wrong, what's wrong with you guys :)?

Brewhaha

I have a couple images of the suggested wiring but it seems a little sketchy... but that's because its open to interpretation as to what passes through the donut (doughnut).

The seller didn't provide the images I just googled it and hey presto... I went to Bunnings for a panel mount plug socket with no luck. So I bought some sockets and switches on eBay now the project will be put back a month until it will reach completion. I-)

Lloyd

Looks like what @olddog was saying.

fadge

@brewhaha looks like your getting all your stuff together good stuff.

***** Just check your parts when they turn up, I ordered sockets like your pics, but on arrival they where stamped 10amp not 15amp and honestly cheap crap- I got a refund and never used them, 3 weeks for nothing.

Sometimes its as easy as going to your local L&H store or Jaycar etc, they will have what you need, and rated correctly as well. A few bucks difference is often not worth the wait for possibly cheaper less quality items.

I decided to use a AU 20mt 15amp heavy duty extension lead. Bought a couple of extra 15amp plugs as well. The plug end was needed anyway cause you need to be able to plug in to a power-point to start with! I used the socket end (that also has an inbuilt power on light) out the other side so I can locate the controller wherever I need without worrying about plugging the element in directly to the controller box. I have about 1mt of cable each end and it would have been better a little extra length in hindsight.

The cable is bright orange/red and very thick insulation, so it does not kink or bend much at all, as a bonus I used the cable to wire my elements, plus used the wires to wire the unit up as well, all 15amp rated. I have 3600w elements, hence 15amp inc powerpoints, 2400w is 10amp. A second element is direct into the power point, extra heat up and faster stripping usage.

Mine controller has been fitted in a computer power supply case, with a green light on/off switch, volt/amp meter, orange element on light, plus fan cooled, this was built prior to @punkin stocking the kits.

fadge

Brewhaha

@fadge looks like a good setup fan cooled where did the pot come from? I have an old PC tower PS and a old Washburn Electric guitar might be able to assemble another controller.

I purchased the 15 amp plug sockets so if I go a bigger element I will be covered I got the 15 amp 20 meter extension lead from Bunnings and I went to my local Electrical supplies and took a 10 amp panel plug socket to the counter and they wanted $17+ for it so I took it back to the shelf and walked out.

The eBay listing showed 10 @ 15 amp sockets only difference should be the larger earth pin and 10 amp will still plug into that socket hope its O.K. Are you still using that controller and I'm interested to know what the SSR is rated and if you still use it and how long you have had it running.

I also have a SSVR I purchased from eBay along with a metal project box 8" L x 5" W 4" H and varistors all before I stumbled onto StillDragon which was mentioned on the Boiler Controller sellers website.

Brewhaha

I have a diagram of how I interpret the image diagram diagram 1 is per image and diagram 2 is what I think but not sure of either /:)

fadge

@brewhaha my controller has not missed a beat at all, buts its not a ssr like the kit or your plan, they both do the same thing however.

I used a prebuilt scr unit sort of like this 10000W 220V Rectifier SCR Electronic Voltage Regulator Motor Controller Thermost @ eBay

Knob attached, so just worked out best way to fit in the case, drilled holes heat sink is screwed to case. I then added the other parts and a old nokia phone charger to run the 12v fan in the case, was warm without a fan, cool as a cucumber with the fan.

Like I said this was before the kit was listed.

Your pics look like the voltmeter will be only showing the power in, not output voltage across the element?

We have a few pics on the site with AU wiring and some US so beware when viewing.

I do have all the parts to build a SSR unit, but it has not been needed so far, I will make it and add it to a semi auto pid based controller one day.

fadge

Brewhaha

@fadge said: Your pics look like the voltmeter will be only showing the power in, not output voltage across the element?

This is what I don't understand... diagram 2 displays current monitor donut on the regulated side active wire, so shouldn't it read the voltage wattage etc of the controlled output side not power in. Now I'm more baffled :))

I thought the supply to the monitor was full current and readings where supplied by the load passing through the current monitor as in your pic of your volt / ammeter. So are you meaning like diagram 3 ?

Lloyd

I think its important to note that 220-240v is different in various parts of the world.
While North America has 220 volt it is split phased over 2 legs (or wires) and each wire has ~110v.

Most of the rest of the planet has 220-240v on only one leg.

Brewhaha

@Lloyd so in my image diagram 2 the donut goes over the active RED contolled wire after the SSR and to power it I just need 240V direct red positive black neutral in Australia ??

If anyone else is watching this thread and knows what is going on please chime in at anytime, I appreciate all the replies I have... I just want to be clear that I'm doing the right thing as I have no real knowledge about electronics. Cheers

dellae

@Brewhaha - It does not matter which leg of the load goes thru the Current Transformer (donut). For the voltage supply to the panel meter - if you take the hot leg off the SCR input (1) then you will monitor the input voltage (ie; the mains supply 240volts). If you wire it to SCR terminal 2 then you will monitor the output voltage of the SCR. However, those cheap ebay meters have a minimum supply voltage requirement (100v I think, check the specs of what you bought) which means it will not display anything until the voltage at the terminals is at least 100 volts.

Brewhaha

@dellae O.K. so If the active is from terminal 2 and the potentiometer is turned back to zero it should read somewhere around 220-240V and if it's drawing around 2200 watts which is what my element is rated at generally speaking, I should get those readings from the meter.

My target is to reduce it to around 1800 watts so the voltage wont drop too low for the meter to read it. I think although a few people have stated that it doesn't matter which line passes through the current transformer I feel inclined to run the active line through it.

The specs for the power meter are listed below.

Voltage Measuring Range: AC 80-270V
Current Measuring Range: 100A
Rated power:             100A/22000W
Operating frequency:     45-65Hz
Energy Measuring Range:  0-9999.99KWh
Power Measuring Range:   0-22000W
Working Time:            0-9999.59hours

Thanks for your reply, Cheers

fadge

@brewhaha most of the info is correct however I just had another look, your meter is a power meter not a simple volts _ amp, it does one more step and displays KWh as well, unsure how accurate with combining a choped up ssr output plus a average doughnut current sensor all for less than $15. But as long as you can replicate a "number" each run it does not matter if truly spot on. Someone else may chime in about keeping the voltage on the input or output with power meters.

fadge

dellae

What @fadge said - agree. Some basic theory - power (watts) = volts x amps - all at the load device. 1st up - whomever wrote the spec is challenged by the english language - 100A / 2200 w??? math does not add up. Going with diagram 3 is the solution - given there is enough voltage (80) to drive the meter. There is likely to be a discrepancy between what is displayed and the actual, unless the meter is a true RMS responding meter (which a lot of cheapies aren't) but it doesn't really matter for hobbyists as you just want to replicate each time as @fadge said. For the price - don't sweat it. Record what you have and use the data for next time. When the budget allows - spring for a true RMS meter - and add another 0 (zero) to the price. I use these cheapies even though I know the limitations, just keep it in mind when quoting actual figures.

Mickiboi

I use Sommy Power and Automation products. The EU9 is for single phase and very accurate. Fully functioned with the works, RS232 if you need it.