DIY Controller Question

GD50

Rough enough is close enough. I don't think you would have much loss at full on and it looks like 20 w but there is no value using the Ssr when you don't need it. As I said - nice job.

kimbodious

@grim said: That looks really sharp, nice.

cheers, I am so glad you can't see the wiring.... I can tidy that up now that I've got it working. The meter is a bit of bling, the bit I really like is the bypass switch

kimbodious

I found this schematic on the interwebs, it really helped me understand how to wire the meter in.

flidget

@kimbodious Many thanks for the image, much easier to understand. I still have to drill my box. I hate drilling plastic, especially straight line rectangles.

kimbodious

LOL, I know how you feel. I used a broken piece of hacksaw blade to wear the rectangle through the top of the box - worked well!

kimbodious

someone once explained about the colour coding of AC flex in a way I'll never forget... "red is hot but brown is shit hot"... try and forget that now ;)

kimbodious

@GD50 said: kimbodious have that setup put it to 50% and also 70 % for us ....

The only reading that makes sense on the meter is for current (pre SSVR)

Potentiometer set to ~50% of total arc.

Potentiometer set to ~70% of total arc.

GD50

Gotta think about that one. Obviously the amplitude of the wave form is still there so either electric ed is right or zero crossing.

The readings with ssr bypassed and with Ssr on flat out show the meter is good for complete waveforms but kinda lose it with modified waveforms during control. Does not surprise me really considering how meters work. The thing of interest is that at 50% on the scale you are at 1/2 power

CothermanDistilling

That is why you used to pay big bucks for 'True RMS' meters as "voltage * current" does not always equal watts, you need the ability to measure the root-mean-square to do that...

be careful when saying 'modified waveforms', our SSVR's to not modify individual waveforms, but shut off complete cycles by turning on and off only at zero-crossings. Chopping the waveform at other points and would cause a lot of RF noise... true RMS should still be able to measure this I believe...

GD50

Yes true re the modified waveforms - it is still a possibility but unlikely. All my flukes ( mostly newer 87 V ) are true RMS and that was exactly the thought line I was considering and alluding to re how meters work.

grim

Isn't ballpark good enough as long as the run to run power input numbers are consistent?

GD50

Yes definitely the case. It's more the workings but now we know to get half power you set the pot to 50 % not 70 %. In the end that's it.

kimbodious

The readings for the pot settings are very repeatable. I'll run the stills as usual but will take note of the meter readings. It will be interesting to see for example what the meter says when I have got the CCVM in total reflux or when I am doing a spirit run on the pot.

GD50

@ClothermanDistilling . I dont think a "True RMS " meter will be able to measure that correctly as it is only really rms-ing the peak to peak part of the sine wave. What we have here is quick on and offs which i am not so sure it will see accurately . You cant even use a Fluke to see the dc voltage of your indicators in a car working as it is too slow.

CothermanDistilling

But each on and off is a full(or half) sine wave, what RMS is made for.... it is not 'chopping' like a triac or SCR...

punkin

Ok, got my meter today, anyone in Australia care to have a crack at updating the wiring diagram from the PDF in the DIY KIT Build Instructions sticky?

Meter here to give away for the best peer reviewed updated diagram. (shipping inside Aus only).

kimbodious

PM sent punx

punkin

Still looking for a diagram.

flidget

Can we include an on/off switch in the update, as well?

punkin

I won't be putting them in the kits and i want the diagram for the kits mate.

flidget

Fair enough. Just saw my opportunity to maybe influence my dream hobby v2 deluxe kit and make it more modular. We don't seem to have a suggestion box thread, so sincere apologies for mentioning it here.

Not just to you @punkin, but is there any reason not to add a switch to the kits - is it a price issue or a demand issue or something else like a technical issue? As a hobby customer I'd like a switch included and would buy one as part of a kit. Why? 'cos I want an on/off switch where I'm controlling the power, not have to clamber around a hot still or dash up to a socket that may be a long way away when things start to go sideways.

But then, where do you stop?

I'd also like to have power connectors on the box not a couple of cable grips and resulting cable tails, something like your PC power cord connections, if they can take the current - so it's easier to maintain damaged cables, pack up and store away etc. A hobby guy like myself doesn't necessarily want permanent cable fixings and have to balance the power box on my head when moving a warm boiler out of the way of the household. My old back and knees don't like bending down and releasing the element - which is also hard wired, and could be terminated with a common connector.

Obviously, I can do all this myself, but it will take me longer to check out all the parts are matched. There would have to be power limit probably of say 5500w or matched to the heating elements sold for the convenience of hobby customers, in some regions. Pro guys will no doubt be custom design anyway, so I'm sort of assuming the control box is an essential hobby thing?

I can see why the current v1 kit is minimum components, lowest common denominator only. It's great to see it evolving with this power meter.

punkin

If you have short leads on the kit then whats to stop you unplugging it instead of balancing it on your head?

I can certainly see where a switch is handy, as you say...Where do we stop. Everyone wants something different thats why we are the modular company.

flidget

I will not be able to have short leads. My suggestion is of course driven by my own selfish needs.

The approach outlined is the modular approach to the power controller, easy (dis)connection between parts. I think that is what SD means by modular / component products, nicely achieved with high quality standard connection points and driven via the high quality tri-clamp that makes it all possible, underpinned by the genius flexible plate approach to distilling. But, currently limited to stainless steel section for still construction end to end, (boiler to product collector).

I hope that SD will soon be looking to expand into these peripheral components, there is potentially a lot of money sitting on the table for these items in the hobby market. It will not help me as I will have DIYed them already, this something to ease the adoption of SD products for those who follow. In business speak I think these types of things are call enablers that reduce the barrier to entry. I want SD to be more and more successful, so I can replace parts easily in years to come. Again, driven by my own selfish needs.

I'm not trying to complicate anyones day, it's just a suggestion and I do not want to divert the AU "diagram for meter" offer.

Littlechicago

I personally don't see a need in knowing this. I am running 6 5500w elements on my 1000l still 4 on diy controllers 2 straight wired to switch. I run all 6 full power on heat up, turning the two non controlled elements off when up to temp. The diy controllers are adjusted according to run type. Knowing the adjustable power values seems like a moot point in my application . Because since I am adjusting the power with the pot according to what is needed ,knowing those power values wouldn't change anything on the way I run. It would be like wanting to know the exact BTU output on a keg/turkey burner setup depending on the flame set-point. Maybe I am misunderstanding this thread IDK. -Drew

grim

I'd imagine consistency and repeatability.

But, if you can do that by setting knob position, the end result is the same level of consistency. I mean, really, input voltage doesn't waver substantially - a pot generally has a high level of precision and repeatability.

I mean, having a number gives folks a way to share run parameters in a more accurate way, which should help the new guys know where they should be operating, but the issue is that even minor rig-to-rig differences are going to make huge impacts on how you operate it. So really only useful for someone else running a nearly identical rig, or just getting ballpark.

grim

Here is the controller I'll be using when I set up my gin rig - Watlow Power Series heater controller. If you want bells, whistles, and information - this is the SCR controller you want.

It can control 3 x 65a heaters, real time monitoring via serial, plenty of different ways to control the specific power levels. Soft start, heater health monitoring, etc.

Big power baby! Thing is massive.

dad

@grim, I was wondering if you figured out how to run it yet. I'm starting to wire one now, but have been perplexed by the operation of the panel.

Myles

There is no point measuring supply voltage or supply current. On all the SSR controlers I have looked at, both the output voltage AND the output current change as you adjust the pot.

You need to measure the voltage across the element and the current to the element.

This dial was calibrated in % output for a PSR 40 - 9 kW controller and a 6 kW element

kimbodious

If you put the CT on the input side you get a repeatable reading for current draw. Is it accurate? Who knows? But the same dial position gives you the same reading for current, i.e. it is repeatable and as such can be used as an index and useful for set points. It may not necessarily give absolute values which would be a huge ask for something that costs less than $10USD.

GD50

I have bought BMS , DDC Bravo Controller ( typically a building management system ) and am thinking of using it to control my still. Plenty of AI DI inputs and also analogue and relay outputs. Dead easy to input rtd's other probes as well as 4 to 20 Ma sensors and also easy to control relay outputs. All the AO's are 0 to 10 v dc. Being more electrical and refrigeration I am at a loss to figure why most SSR are 4 to 32 v dc input voltage and the significance of this range of control voltage.

Carlo Gavazzi do make a range of SSR with a 0 to 10 vdc control input but they are really expensive. Anyone have a way to change a 0 to 10 output to control a much cheaper 4 to 32 v SSR but as said what is the logic of 4 to 32 v control in the first place. @ClothermanDistilling @grim