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Re: Control Freak
Posted:
Sat Nov 08, 2014 12:36 pmby Meatheadinc
the system can be overridden to lock out the sensor if necessary.
I would like an easily removable grate / top to allow access to the sensor for drying and cleaning.
The catch cantainer I would like to have a conical base to direct liquid to the sensor although if I cannot source such a vessel then a funnel my be used as 12many suggested
I am hoping to use glass or stainless however as it is not for drinking ( small spill containment) I may utilise some synthetics
Re: Control Freak
Posted:
Sun Nov 09, 2014 10:06 amby Maritimer
Hi Meathead,
Meatheadinc wrote:Not a bad idea.
I am looking at other setup as I know the current tray is to large.It was used only to bench test the sensor.
Looking for a neat tray grill combo ,
This is the setup I'm using to collect product. Instead of overflowing, the product just passes into the next jar.
http://homedistiller.org/forum/viewtopi ... 2#p7215352Gotta get a real flow switch!
Nowadays I put three jars in the ceramic casserole dish, so even if they do overflow, no big problem. The finished collection system will guide overflow down a pipe to a sensor, which will put the still into equilibration mode. That's for next summer. Got the first snow today.
Have you been thinking about logic control of some sort? A few relays could do wonders.
M
Re: Control Freak
Posted:
Sun Nov 09, 2014 3:07 pmby Meatheadinc
Hi Maritimer
I did I fores and heads Volumetric collection on an old 2 LM based on the same principle as yours ( although not as elegant)
I did it with lengths of 1/2 and 1' pipe Fores 100ml then heads 250ml before then overflowing down coil to collection vessel.
it worked ok but only for known washes ( head /fores trap left of column. ((twin leigbergs right))
2' (528x800).jpg
the taps were for emptying or left open for manual operation..
I was worried that this system would encourage smearing of fractions hence why I only used it for fores and heads, have you experienced this ?
Maritimer wrote:Have you been thinking about logic control of some sort? A few relays could do wonders.
Yes. I am currently in dispute with a vender/paypal regarding some contactor blocks ( NC + NO relay blocks) and some relays (DC trigger) so hopefully by Christmas I will have it finished.
Think I have got my rain sensor sorted . pic to come
Cheers
Re: Control Freak
Posted:
Sun Nov 09, 2014 3:28 pmby Meatheadinc
Rain sensor/ overflow container/switch
rain s fin (600x800).jpg
Top grill is the base of a stainless steel vegetable streamer - see sides in foreground
rain s dish (600x800).jpg
I found a small porcelain dish($1.50) with a concave bottom to direct any liquid to the sensor - grill attached
it was because of the concave base and stability that the wooden base was added
rain s grill.jpg
sensor can been seen in the dark patch in the centre of the bowl
rain sen (600x800).jpg
now a bit of sanding and polish and its done
Re: Control Freak
Posted:
Sun Nov 09, 2014 10:48 pmby badbird
Nice work on the controller Meat, I'm jealous my attempt at one keeps getting sidelined by other pain in the ass stuff at the moment. :doh:
On the subject of flow switches for what it's worth, if anyone is looking at using those $6 black plastic ebay ones. They are probably ok for mains pressure cooling but unmodified, they are useless when used with a low pressure recirculating pump. Luckaly they use magnets repelling each other in place of a spring so it's simple to take the small one out and Mount the flow switch vertical so gravity is doing the job of the magnet. Tales bugger all water flow to turn on the switch then :handgestures-thumbupleft:
Re: Control Freak
Posted:
Mon Nov 10, 2014 1:10 amby Maritimer
Hi Meat,
Meatheadinc wrote:I was worried that this system would encourage smearing of fractions hence why I only used it for fores and heads, have you experienced this ?
Once you have passed the fores and heads, the smearing is from good to bad. What I mean is, if you start up the collection bottle system after you've taken the fores and heads, the product can only get worse, so the smearing is putting good product into bad. The smearing is very small, though. The tube between the takeoff and the top of the vapour lock is about 3 inches X 1/4 inch dia = 0.8 cubic centimeters. The jars are 500 cc, so any smearing is at most 0.16%. The bad stuff can't get into the previous jars because of the air lock.
If you want to discuss relay logic, you can PM me, or we can do it in this thread. Others might be interested, too.
M
Re: Control Freak
Posted:
Mon Nov 10, 2014 9:33 amby Meatheadinc
Thanks Maritimer
your input and knowledge is much appreciated :handgestures-thumbupleft:
@badbird If the new flow switch I have ordered does not do the job I will be using your idea. thanks :handgestures-thumbupleft:
Re: Control Freak
Posted:
Mon Nov 10, 2014 10:10 amby Triangle
Very impressive build there, nice and neat too. You'd put some of the sparkies I worked with to shame!
Re: Control Freak
Posted:
Mon Nov 10, 2014 1:21 pmby Meatheadinc
Thanks TGS
all wired up except I chipped the edge while chiselling the inlay/cut-out for the electrics :angry-banghead:
rain s elect.jpg
black cover is from a old lamp and is press fitted
good thing is its hard to see to chips ( especially from this angle :handgestures-thumbupleft: )
rain s f2.jpg
Re: Control Freak
Posted:
Mon Nov 10, 2014 7:11 pmby Potmash Boka
Nice build there. Just out of curiosity, why did you go with RTD's and not Thermocouples. RTD's are slower to respond to temp changes than Thermocouples.
Re: Control Freak
Posted:
Mon Nov 10, 2014 7:57 pmby Meatheadinc
I have a couple of thermocouples and found that they were not very stable and constant in testing.
although thermocouples have a larger detection range and have quicker response, RTD is not slow and is more accurate and repeatable with our target range.
Re: Control Freak
Posted:
Mon Nov 10, 2014 9:14 pmby badbird
The problem with thermocouples is they don't work well through standard plugs, sockets and lead extensions so should be connected directly to the back of the PID.
At least with RTD's the leads can be easily extended within reason and so long as all 3 conductors (including pins etc in plug and sockets) are the same length and resistance all should be well.
Re: Control Freak
Posted:
Mon Nov 10, 2014 10:35 pmby Meatheadinc
badbird wrote:The problem with thermocouples is they don't work well through standard plugs, sockets and lead extensions so should be connected directly to the back of the PID.
Maybe that was the problem. I did cut a thermocouple lead off a probe to use to connect to the XLR plugs (Mic Plugs, 3 pin) but still found them to vary greatly.
The NTC thermocouples ( wired as above) on the lower 2 PIDs and they sway in temp about 0.8 deg. (0.4 each way within about a second- thus faulty signal)
The NTCs are for the second "heatup" element (auto cut off) and for mash control and the temp swing will not be too much of a problem although if building again I would swap the lower units with something RTD compatible.
Re: Control Freak
Posted:
Tue Nov 11, 2014 6:52 amby badbird
It sounds like the leads are picking up noise if both the PIDs with thermocouples are doing much the same thing, I guess the cables probably need better shielding.
The joins in the thermonuclear cable should produce a lot vaguer slower response as you kind of end up measuring the temperature at the joins as well as the end of the probe.
Wikipedia explains it better
The most common error in thermocouple construction is a circuit extension with dissimilar metals such as copper wires. As explained in the Principles... section above, it is crucial to know the temperature at this point of transition, as this point is the very definition of the reference junction. All further junctions are irrelevant past the point where the switch to copper is made. The mistake is in making this junction without measuring its temperature, and then proceeding as if the reference junction is a different junction nearer the voltmeter; when the compensated voltage \scriptstyle V + E(T_\mathrm{ref}) is calculated, this fake reference's temperature is used in place of the actual reference temperature. If the desire is to make an extension without needing a thermometer at that location, then extension wire (see below) may be used; this allows the reference junction to be made closer to the voltmeter.
Re: Control Freak
Posted:
Fri Nov 21, 2014 11:41 amby Meatheadinc
badbird wrote:It sounds like the leads are picking up noise if both the PIDs with thermocouples are doing much the same thing, I guess the cables probably need better shielding.
You are right I have re routed the thermo wiring and am getting a much more stable reading. I am using a cut thermo lead for extension so the only real joint is the XLR plug, solder joint ( mic plug) Now the wiring is re-routed I don't think this will be a problem
new flow switch arrived today
flow switch.jpg
I just wish my relays and contactor would arrive so I can complete this project
Re: Control Freak
Posted:
Sat Nov 22, 2014 8:24 pmby badbird
I am using a cut thermo lead for extension
Good solution :handgestures-thumbupleft: , didn't think of that.
Is that a flow sensor or a solenoid type valve??
I'm still waiting on a relay and bits from China or somewhere, but i guess it doesn't matter much, everything else is packed away in removals boxes for the next month or so anyway. Stocks are getting low and with Christmas coming..... :crying-blue:
Re: Control Freak
Posted:
Sat Nov 22, 2014 10:05 pmby Meatheadinc
Badbird its a flow switch. a DC paddle switch the 240v one I had earlier would not trigger at low flow. this unit triggers when I lightly blow through it and should do the job. ( as yet not application tested ( bench only))
my solenoid valve co be seen in earlier posts
Re: Control Freak
Posted:
Fri Nov 28, 2014 8:03 pmby Meatheadinc
my contactor block arrived today. :-D
contactor (600x800).jpg
also some XLR plugs. Finally I have all the holes filled. :handgestures-thumbupleft:
outside (600x800).jpg
Now just to wire it up and it will be finished :happy-partydance:
Flow switch N.Open. triggers with flow. ( no signal= no flow.... flow = signal)
this will work by connecting my element output to the N.Open port of the contactor and using the relay from the flow sensor to trigger closed circuit for normal operation and opening the contactor when " no flow" is detected
The rain/spill sensor will be added to the dephleg control relay to trigger the solenoid and achieve reflux - if issues with slow response are experienced, I will swap this system to disable the heating elements.
If only I had some larger circuits to run this this controller at its full potent instead of locking out function to 10a per circuit :-|
Re: Control Freak
Posted:
Fri Nov 28, 2014 9:59 pmby badbird
Nice work Meat
You need some more xlr's for that blank spot though :teasing-tease:
I know where you are coming from regarding just having the one 10amp circuit, its just not doing that box justice. Sooner or later i'mm gunna have to get a 25amp or so circuit to the garage as well, for the, errr, 'welder' :D
Re: Control Freak
Posted:
Fri Nov 28, 2014 11:23 pmby Meatheadinc
HI Badbird
The control box runs 2, separate 10 amp input circuits, however each circuit has the potential to run more. The wiring was done so that all most all functions are wired for 15 amp.. both input circuits have " either or" switching for 2 functions. (
Given adequate power supply this box could run my still (up to 20amp total) and an electric brewery (30amp) simultaneously. however with the current restraints it can only do 20amp total :cry: