Electric, robobrew, variac, help

[barbasol]

done a few batches of beer on a robobrew and saw the still attachments. Excited for electric distillation and read numerous threads on it. Mostly how pid controllers can’t just be set it and forget it. I’ve done 10ish runs over propane with a quarter barrel and pot column setup so I’m familiar with a watchful eye and adjustments. 2 options I’m thinking are to control the robobrew temp and raise/lower as needed based on output. Other option which is my main question: can I crank the robobrew to 240 (high) and then plug in to my variac to control? I have no electrical knowledge/background

[Yummyrum]

Not sure what kind of Variac you have .
Mine is typical of an Electronic Service Department and has a maximum rating of 2.5 Amps . No way I would plug a Boiler element into it as it would burn out .

A Variac is an adjustable Auto transformer . Are you "loosely " using the term variac to refer to a power controller ?

[Pikey]

Agree entirely with Yummyrum - Not the right tool for the job !

Cheap Chinese "Speed controller" - Search this on ebay

"10000 speed controller"

They work fine for me - running 2 1/2 kW - but a "5000" burned out after 20 minutes, so best to over-rate them - It doesn't even get hot and I don't bother with a fan.

[barbasol]

Thanks guys! I’ll check it out

[shadylane]

Is this the robobrew your using? https://www.williamsbrewing.com/ROBOBRE ... P4338.aspx" onclick="window.open(this.href);return false;" rel="nofollow

Based on the add, a variac rated for atleast 15amp would be needed
https://www.amazon.com/Beleeb-Variac-Tr ... rds=variac" onclick="window.open(this.href);return false;" rel="nofollow

[Antler24]

Agree entirely with Yummyrum - Not the right tool for the job !

Cheap Chinese "Speed controller" - Search this on ebay

"10000 speed controller"

They work fine for me - running 2 1/2 kW - but a "5000" burned out after 20 minutes, so best to over-rate them - It doesn't even get hot and I don't bother with a fan.

I second this. I'm powering a 5500w/240v element with the 10k version and it's been working great now for 3-4years

[barbasol]

Alright more details and thanks for the replies. Robobrew has a 1000w and a 2nd 500w element, 110v and im on a 20amp circuit. My variac is rated 20a so I think my equipment is all good. 1500w, 110v and 20amp=all good right?

What I’m really trying to understand is if I set my heating element temp controllers to 240deg (or what I think is full time on} can I use the dial on my variac in a similar fashion to a propane burner with similar fine tune control. Counter clock turns the heat down and clockwise turns it up?

Please feel free to point me to more reading on electric distilling. Thanks all!

[Yummyrum]

it's hard to say for certain . Obviously from the control panel on the Robobrew , it has its own electronics that control the element . That electronics will be powered by the incoming 110V . How Critical it is that it needs 110V will be the decider .

So say you have turned your external Controller down and its only supplying say 75V , the internal electronics may throw its arms up and not function at all ....lights on control panel go out ..... Therefore no power will get to the Elements regardless of what its set to .

A lot of Controllers in this application get their power from the peak of the mains waveform . This brings me back to querying when you say you have a Variac is it a true adjustable transformer ( you'll know because it will probably weigh about 10kg if its able to supply 20 Amps ) or is just an electronic power controller ?

If it is a True variac then you may experience the cutting out issue I mentioned earlier as you wind it down as it will supply a True sinewave but of variable voltage .

If it is an elecronic controller then it may be one of two main types , a phase controller , which will supply a chopped up version of a sine wave but will have a higher peak voltage than the Variac for the same power .

Or... it could be a Burst fire controller which will supply the full mains cycle periodically but the peak will always be there , so statistically your internal controller should cope very well .

Bottom line , plug it in and try it . .......my only concern might be that if you run it at a lower power input on a phase controller , it may damage your internal controller in a similar way to how some Volt /Ammeters blow up when run off a phase controller .

If it was mine , I would pull it apart and wire up a switch to the bypass the electronics when using your external controller

[barbasol]

It is a true variac. Guess I just need to fill er up with water and see what happens! Worst case I can unplug and just use the Robinson by it’s self unless I break something. And worse worse I dump into my keg still and go back to gas. Thank you yummyrum for your input

[shadylane]

Just a thought
With a 9 gallon boiler and 1500w of power
A controller may not be needed

[Antler24]

Just a thought
With a 9 gallon boiler and 1500w of power
A controller may not be needed

Good point shady. I did my first 12 gallon spirit run at 1375w and had to insulate the keg and column to get running at the speed I wanted. So, it may be a little faster than ideal for a spirit run, but I think you'd be ok.