Decided to build my own fancontroller, the only problem now is that i can only find maplins that stock these variacs and there web site says there out of stock and mybe re-stocked with the next 28 days which is a nearly a month!, anybody know where i might find these things ? proving harder to find than rockin horse shit, must say all this fan controlling lark is becoming a royal pain in the arse, ho and i've tried ebay before anyone asks, any help welcome
Rj
e2a: just checked rs components they have em in but there nearly half as dear again as maplin.... just cant win

Here's one of my posts from another related thread, here.:

The place the description and price quotes are from is here. [www.dealec.co.uk]

Ebay saves the day again got me 2 of these for £67 brand new and rated to 1 amp...sorted

just remember to put them in an ip56 rated box... coz the suckers CAN KILL...

A big thanks to Scraglor for his advice on fan control and electrics, credit goes to him for the diagram, what he doesnt know about motors and switches probably aint worth knowing mucho karma to you sir, the only thing i need to clarify and were unsure about is the switching from high to low regarding the relay on the thermostat, i've included 2 diagrams one switches the wrong way round meaning when it gets hot it will go to minimum extraction, and the other is the correct way ie switching to maxium extraction when it gets hot, my gut feeling is that its the one with the live out on the LEFT handside of the variac, any chance some one with this thermostat can confirm it please, Rj

And the winner is....the one i didnt think it was, always pays to ask , thanks to Ot and Scraglor for their advice, when i get all my bits and bobs together i,ll post up the final results,
Rj

Actually this will only work correctly with a relay as terminal 1 needs a permanent 240, it will work to some degree but the temperature range will be huge inbetween switching, so its back to the drawing board and off to bnq for a different stat, again many thanks to ot and scraglor for their pm,s , eventually i,ll post a winning diagram when i get a stat that will work, Rj

Ah crap thought you're quest was nearly at the end there Rastajedi mate good read and good feedback .
Wonder if we can get a mod to combine some threads as im watching three at the moment & might be help for future ref we got this thread here trying the variac to thermo , thread HERE wiring for the 5 step & h4z3's thread HERE wiring the Wac1 and finally the B&Q dimmer/thermo HERE All great reads with very helpfull advice .

Cheers Sheriff, i,ll get there eventually, i've considered all the different set ups and it would seem for the money that this method is probably the most tunable without all the effects of buzzing fans etc, the 5 step and wac1 all seem to be good methods that will serve well, but i like the flexibility that the variac offers and the silence they employ, certainly wouldnt advise the primair type controllers or dimmer switch methods theres just too much bad feedback about the fans buzzing and the potential to burn them out or worse, there are inherent risks with the variac but if used properly and they're set so they dont exceed the max volts that the fans require everything should be fine, its basically the same control method as the one that airforce fans use on there controller but with the added thermostat , but at a considerably cheaper price, i believe there charging just short of £100 for a basic contoller with no thermostat overide, good mind to start makin them, i'm sure theres a market for a decent variac fan controller at a reasonable price, Rj

Dont no if you have been through the h4z3
Theres a great read from whazzup on his findings on the smaller rvk's as to there output good stuff . And im sure there a huge market mate

Cheers Sheriff, good read indeed, thanks ,Rj

does your thermostat have a spare terminal? if so you can disconnect the anticipator from terminal one/common and connect it to the spare, then connect mains live to it, then run with the original circuit, unless you've already got the other thermostat.

i havent bought one yet mate, i suppose it would be easier for me to just pick one up from bnq, if the thermostat is accurate then i,m not too fussy, the more idot proof the better really, never seen the honeywell one so i dont know if you can tbh, thanks anyway Scraglor, Rj
e2a:if it will fit could i just put a piece of terminal strip in ?

well you can connect it any which way, as long as it's safe, i've never seen a honeywell stat closely so i dunno how easy it would be to do, i thought you already had the honeywell stat? if not just get the b&q one without the resistor. those resistors are designed for large areas where the heat takes a long time to get from your rad to the stat, or cold air from your ventilation if cooling, so in a smaller space a standard stat will do anyway

No mate still doing the homework/research so to speak, i thought it may have been ok to adapt since other people have used it successfully , but i,ll follow your recommend saves fannying about ,Rj

Whey hey variacs finally showed up, there alot heftier than i thought they would be for a 1 amp rating, looks like someting that belongs in frankensteins lab, gonna need a strong enclosure for these beastly things, Any sparkys wanna confirm the wiring ?

edit: not sure to be honest, it can be set up for different output scales. i.e. you could have 0-240v or 20-270volts (depending on the specs) do you have a make n model no. or some literature that came with them?

what are the wires connected to two and four? 3 is obviously your output sliding scale, i'd say connect live and neutral between 1 and 5 for 0-240v output and live and neutral between 2 and 5 for 0 - 270v output, but those wires are throwing me a bit

ah ok, i see, they're your connections?

connect live into 1 and neutral into 5 will give you 0 - 240v output, connect live into 2 and neutral into 5 will give you 0 - 270v output

edit, the other taps are for various input voltages

but anyway, just go live into 1 and neutral to 5 output is 3

you'll get a scale of 0 - 240v if you connect live and neutral between 4 and two like you have, but you're putting full mains voltage across two few windings so you'll put two much current through the tranny, also move the nob too far one way and you'll get more than 240v

EDIT: here's the pdf:

http://www.claudelyons.co.uk/tech.pdf

take a look down the bottom of the page and it shows all the different configurations the transformers can be used for, seems 6 is used in conjunction with another tranny for small range increasing/decreasing of mains voltage, and the various other terminals are for all different connection configurations for fine tuning voltages and bla bla bla, quite a handy bit of kit you got there, 100squids + when new!

As i understand it, according to the pdf, 1 is neutral in 5 is live in and 3 is the variable live output ?


I,ll get the soldering iron out tomorrow , mount em up and do a few tests with the old fluke meter, Rj

Had a chance today to nip out and get an enclosure, thermostat, cable glands today all off the shelf at bnq, cost around £32, so far that puts the build cost at £99 , still some £50 cheaper than the systemair reu unit which doesnt come with a stat, i already have some terminal block kicking around in one of my many scrap boxes along with a few ties, nuts n bolts clips etc

First thing to do was make a template to match the mounting holes for the variacs and then apply the markings on the lid box, i just used apiece of clear rigid waste plastic for this, cut a hole and placed over the center splindle of the variac so that it lies flat on the mounting holes i've ringed in red which ones i mean, then applied the markings to the lid and drilled out, as you can guess they didnt line up exactly bang on, but by placing the variac and marking with a pen where they needed a slightly wider hole and then correcting with a gentle router like action with the drill bit, i also drilled a couple of holes for cable fixings with some old pyro clips, next i soldered the wires to the variacs and bolted them in place on the lid, threading and marking the cables through the pyro clips, so basically its 2x common negs, 2 x common lives and 2x variable returns, got alittle bit too late tonight to do it all in one go will finish it off tommorrow,Rj

ok , now for the base, which consists of a four way plug outlet for the fans to connect to , three cable glands , one for mains in, the other for the thermostat, and the other for the 4way, i decided to put an inline 1amp fuse between the mains and the variacs to stop any overload, all the neutrals come together under 1 terminal, as does the earth from mains in and the 4way going to the fans, the live mains in connects to the 2 live in's on the variacs, the 2 variable outlets from each of the variacs connect to terminals 1 and 3 on the thermostat and terminal 2 is your live output to the fans..easy Rj

That's a sweet, neat piece of kit you've built there, RJ.

Cheers Scribble, tbh i could have made it cheaper by using just one variac and having it switch to 240v on max , i would have also been able to use a small housing which would have saved a few quid, but since i cant be there 24 hrs it takes alot of the stress away knowing that the temps should be quite stable at lights on and off, i reckon it would cost around the £55 mark for a single variac controller, more money could be saved if the fans where hardwired in, but by having the 4 way it means you dont have to unscrew the thing if you want to add more fans or move to another grow room,
Rj

dude, sweeeet!

Thanks Whazzup, and a big thank you to you Scraglor for inspiring me with your knowledge and advice...orders are now being taken... Rj

Spot on Rastajedi see you have been a busy boy , i have strange visions of you though with that Santa hat on working away feverishly , like a little elf , wait a min it don't look like a vision no more , top job mate .

Hey Sheriff, so you've been havin fantasies about me in my hat , i have mate, been busy that is, i've been lucky to get the house to myself over the last few days, what with mrs Rj n the kids floatin around, i would have liked to use a more stylish housin than the borin grey thing from bnq, but with christmas and a whole new grow room to sort its been a case of get it done and dusted, thanks for the kind words buddy , Rj

Hey ,well chuffed thanks for pinning, Rj

Nice

Cheers Freddy , give it a whirl mate , really is a doddle ,Rj

This may save alot of searchin if your lookin for a variac other than the one offered by maplin, R.S.
about the only two places i can find other than ebay, but R.S. looks like the better bet folks
Rj

For anyone like me, who read through all this and thought "Ooh er, don't fancy trying to wire something like that, might kill myself/burn the house down", there is an easier option. The Airforce fan controllers are variac-based, you can find the basic one without thermostat for 95 quid in several online growshops, though unfortunately not Greens at time of posting. I've just received mine, my fan is no longer humming, and I didn't have to wire anything - just plug the fan into the controller and the controller into mains, sorted. It doesn't need to be an Airforce fan, it will work with anything.

Clairtronic make most of the variacs sold in Maplin or RS Components so why not buy direct from them. They'll quite happily sell to the public although you do have to pay by direct bank transfer but it's cheaper than paying a middle man for one, it's where I buy mine from

You can get them in enclosures or for the more daring/suicidal they come un-enclosed.

As squirrel says dont take it on unless your confident about wiring etc, otherwise it really is quiet simple to diy and you will save over £55 instead of paying hand over fist to airforce

this info would have been far more helpful a month or so ago ..

Well I only just read the thread yesterday and it's there now for anyone else who needs it.

Let me just see if my time machine is working............... Sorry it's not

Rj

Hi,

Clairtronic are £37 for the 0.7A open type variac (dont know about delivery)
Maplin are £31 and offer free delivery on orders over £35.

I was wondering if you could give me some input on a quad variac design i was thinking of building. Do you think its worth the extra for the additional functionality?

>>Brief<<
Build a fan speed/enviroment controller that can balance intake out-take. Would maintain the balance, but increase fan speed as T rises.

<<Build>>
4 variacs
1 central heating thermometer
1 humidistat
1 fan or oil filled heater

So on both intake and out-take channels, there would be a min variac and a max variac. The thermometer would switch between these two settings. The humidistat would turn on the heater when humidity rises and T is on the low setting.

I would very much appreciate some feedback on this before i go buy all the bits. Specifically, do you think its worth including the extra 2 variacs and humidity controll?

Any help, thoughts or advice much appreciated.

BaB

if you can source two variacs similar to the ones rj has with fixed voltage outputs you could do it with just two, or if you're handy you could use the maplins variacs and attach an extra tap, pretty simple to do, you'd just need a plastic strip to attach to the spindle with a terminal soldered to a metal contact glued to the end of the plastic strip, then just fix it at whatever voltage point takes your fancy, voila you now have two voltages from one transformer, just switch between the two

Hi,

Could you use a 100w rheostat to set the offset of the fans then 2 variacs to determine the HIGH and LOW speed settings?

Im concerned about the weight and size of the module with 4 variacs, and the offset of the fans should be about the same drop in V at both the HIGH and LOW speed settings.

Any thoughts on this? specifically what size of rheostat (if possible) should be used.

BaB

u really like that ATc unit dont you whazzup... i know i do.... i think they have em back in stock now- Im waiting for them to phone me back to confirm and then im ordering mine-to go with the 5step from ebay.
hows your setup with the ATc comjing along then??

gutted that u aint got it yet- i ordered mine yesterday at about 4pm and it got here this morning-mind you i hadnt seen the hong kong seller and I waited for monitors direct to have em in again....
Its a lot chunkier than I expected..... Ive ordered the finder relay and socket, and the 5 step controller(that ebay seller has some 2.2 and 5 amp ones now) as well-they should be here monday/ tuesday i guess.... then theres just the enclosure and cable glands to get-oh and some heavy duct power cord/sockets and a panel mount fuse holder.
That 5 step in its enclosure is as big as the ATC, so i dont know if im going to be able to take it out and put it with the ATC in 1 big enclosure-might not be able 2 get one big enough for em to go in together..... Ah well ill get it sussed....
I hope ur ATC arrives soon and you dont get stung for the import taxes....
toke it easy

In the instructions that came with the ATC, it mentions that the unit may suffer from RFI problems and should be kept away from equipment, would making a shelf and putting brass mesh all around the shelf to form a farraday cage help if the ballast was on that shelf... apparently it could casue it to switch incorrectly or even reset(ive had that with digital timers often) Would ferrite clamps help?

what equipment do you have nearby that would emit rfi? i wouldn't worry about it mate, unless you're using a cheap electronic ballast or have computers connected via routers in the room or other similar stuffthere wont be much rfi around

In the instructions, it mentions the power cords of stuff including itself and the equipment to be controlled, says to keep away from any equipment...also there is a couple of mentions on aquarium forums (the primary purpose of the ATC800 is for aquarium temperature control) about close proximity to halides sending the readings screwy i wondered if all HID's would.... It mentions voltage variations could send it screwy too.
I also wondered if mounting the 5 step controller into a single housing with it might cause these types of problems.... Its going to have to go all in one housing I think, because there is no space in the 5-step housing for the relay to go inside it-although it would be nice to use those aluminium chassis that airforce use(maplin) and make it look like their units with a shiny alu housing each. ill decide by next week when i get paid and will be ready buy the last bits n pieces(such as housing/s, plastic rivets, and cable glands) to put it together... If id been able to fit the relay in the existing housing for the 5 step, I was going to fit the atc in a housing on its own and mount them both, along with my timers and power points to a nice piece of polycarbonate or something.... All my controls mounted to one board instead of stuff hanging from screws in the walls all over the place. Will probably still do it that way whatever...do you think polycarbonate is a suitable material...I was going to go with MDf but thought polycarb may be safer??

humidistat fan??

Hello All read through this and the other posts i could find

wat im thinkin is:
is it possible to use a bathroom humidistat fan with a cheap speed controller
or is tht impossible becos of three phase??

really cant afford an expensive setup

am using a humidistat as i speak but it goes off at night coz its way to loud
(a bit of buzzin wouldnt be this bad would it??)

dont want my door smashed in


If any sparks could think of a way it must be worth a shot

my fan is 240v 15watt so less than 1 amp
(i believe)

could a 1 amp speed controller run this

Greatly appreciate any help Allen Key AKA. Metric Hex

a humidistat fan only comes on when humidty gets too high, so you could possibly cook your plants if temps get too high and the humidity never gets high enough to turn the fan on, but the main problem is smell, you'll need a carbon filter to get rid of the smell when the plants are in full bloom (and trust me, they absolutely fucking stink, will stink your entire house out) and little bathroom fans just don't have enough bollocks to blow through a carbon filter, so you need a good centrifugal fant do the job i'm afraid. you can get centrifugal type bathroom extractor fans which will be good enough for REALLY small grows, but anything over a few feet cubed and you're gonna need some proper ventilation