Solenoid Valve

Whitecap

Forgive me for being short on understanding the PID and the proportional control valve, grim.

I thought my PID only had on/off control; what settings allow the PID to proportionally power the valve?

grim

Sorry the Auberins unit you list will not work, you need a unit with a process control output, either 0-10v or 0-20ma, to match the valve.

If you want to use the Auberins unit, I'd suggest you use a solenoid valve, something like an Asco red hat. I'd use the SSR output and set the cycle time to the minimum, 2 seconds. Don't oversize the valve, you'll have a headache with a 2 second minimum cycle time if you do (or you'll need to add a restrictor/valve to slow flow).

Unsensibel

Depends on your controller.

The basic one's are on/off pulsing with a certain frequency and duty cycle - for example with a 1 Hz frequency and 40% output, the output would be on for 0.4s and off for 0.6s.

There's more industrial versions available that instead of pulse give out either 0-10V or 4-20mA instead. That output Then fits directly with the valve input.

Whitecap

I can work with that, grim.

Is it right to say this setup will make less noise (without the chinese water torture of a clicking solenoid)? If so, then it seems to be so worth it.

grim

Yes, the Johnson and Belimo valves only make a little whirr. Also, during a run they are only ever making minor adjustments up and down, so they barely move around. You'd really only ever notice them when you were changing the set point temperature on the controller and they had to adjust to hit the new set point.

During my runs, they start closer to the closed side, and as the coolant tank heats up through the run, the valve position gradually goes further open.

If you are using mains water, and don't have great water pressure, you might notice the valve adjusting as water is used elsewhere in the house. Flush the toilet, the valve opens to compensate… :))

fadge

@grim are these suitable?

I'm unsure of all the specs in relation to CV values, what range should we be looking at, as it seems most control is at the lower end of flow, my system is less than 1 lt/min.
I'm running a 4" rig on std SD lines, via recirc 1000lt tank feed with a submersible pump.

These ebay deals are great until shipping kicks in for AU, group buy would be good, or a local member who can forward at a reasonable price perhaps?

The one above is us$25, plus us$55 for shipping.
I would be willing to buy/hold/resell units if suitable, or perhaps @punkin perhaps?

Cheers Fadge

Whitecap

@Unsensibel said: Depends on your controller.

The basic one's are on/off pulsing with a certain frequency and duty cycle - for example with a 1 Hz frequency and 40% output, the output would be on for 0.4s and off for 0.6s.

There's more industrial versions available that instead of pulse give out either 0-10V or 4-20mA instead. That output Then fits directly with the valve input.

Is there a unit you would recommend to get the job done, Unsenibel?

Mickiboi

@Whitecap said: Is there a unit you would recommend to get the job done, Unsenibel?

It's a pity you are not in Australia. I have a box full of C809 0-10V and 4-20mA models I want to start getting rid of. Would be 25 plus postage.

Whitecap

Cool, I'll send you an email now, Mickiboi.

grim

@fadge - Good deal but way too big (1" to 1.25") or a 4". It would work, somewhat, but you would probably only use 0-20% of the range, realistically. Given that @CothermanDistilling is getting good results on his 8" rig with the 1/2" and a beefy pump, probably no reason to go as big as 1" unless you have 8"+ and very long recirculating lines.

If you are on city water with good pressure, the 1/2" is more than sufficient for even a bigger rig.

Mickiboi

@fadge that valve is 1 1/2". Way too big for your 1 litre a minute. That's a very small flow you have. At that flow you need a 1/2" with a low CV like under 0.5. Try belimo. Ring belimo in Melbourne and ask for Raf Tanzimat. He might be able to help you. But be prepared to pay for it.

grim

I don't know what other lines might be more common down there. I know Siemens has a line it I don't know the codes off hand, they are rare out here.

I have a Belimo LM24-SR equally as nice as the Johnson but uses 4-20ma control.

Whitecap

Anyone have an opinion on these PIDs?

TA4-VSR analogue output 0-10V

dellae

@Whitecap
I got the TA4-INR 4-20mA analog output unit.
Documentation is pretty scrappy (gingalish is up to the usual level) - I lost mine so can't calibrate it - asking the seller for an electronic copy was a waste of time (No english).
Out of the box temperature is out by ~2C.
For the price they seem ok - I haven't checked the accuracy of the 4-20 loop yet.

fadge

@Mickiboi said: fadge that valve is 1 1/2". Way too big for your 1 litre a minute. That's a very small flow you have. At that flow you need a 1/2" with a low CV like under 0.5. Try belimo. Ring belimo in Melbourne and ask for Raf Tanzimat. He might be able to help you. But be prepared to pay for it.

Yep I misread that listing, was searching for 1/2" and that popped up and only half read the listing before posting on here! PM = premature posting.

Got a rough idea on expected cost new via belimo ?

I will pm you about those pids as well, as I would take 2 or 3 perhaps to play with, and having an expert to assist with setup is a real bonus, and all in english !!

As I mentioned prior, it appears if we can source or perhaps group buy some suitable valves at a fair price, then quite a few of us would try to build semi auto control units.

I cannot get my head around the idea of just using on/off valves with clicking and such then getting the tuning and correct cycles, compared with proper variable control valves that will simply work as we need or similar to our manual needle valve controls.

No offence to OD and his controllers,(or others designed) but it seems that they can work fine for our use, but with some limitations or noise.

fadge

Mickiboi

@fadge Belimo, you are probably looking at about $300 for the valve and the actuator. It comes with a CCV insert, this allows you to characterise the flow curve to your particular needs. Not cheap I know.

grim

In terms of PIDs you guys should keep an eye on in the used/surplus market:

Omega CNI16D5X - The 5 is important, it means 0-10v/0-20ma output. Replace the X with 2, 3, or 4. The Omega has dual control outputs. 2 means SSR, 3 means Relay, 4 means 0-10v pulsed DC (for SSRs requiring pulsed input). If you can find the -EI variant under $100usd surplus, buy it immediately. EI has the web server/ethernet kit, plug it in and point your iPad right to the web page. It's not too pretty (old school), but it works.

I love Omega gear, it's high quality, accurate, easy to use, and has great instruction manuals.

Other unicorns to look out for are the Watlow F4 - Specifically F4PH-FFAA-(etc) or F4PH-FFAE. The FF is important, that's dual process outputs. Where it says "FF", you want at least 1 "F". There is a ramping variant FPSH that will also work. You can program the ramping controller to maintain heads compression timing and then ramp downwards to collection.

Eurotherm has some beautiful units as well, I won't go into the details. The unicorn of unicorns is probably the Eurtherm nanodac. As with the others, you need to decode the specific models to understand the input and output variations. If you see a nanodac in the right configuration for $200-300, again, buy it immediately, sells for $1200-1500 new.

If you look these up, you'll find they are probably expensive, don't buy them expensive. Wait till you find a unit, where someone doesn't know what they have and sells it too inexpensively.

I picked up 2 Omega CNI16D53 Ethernet controllers for $75 bucks last year. Both together would sell for $700 new.

BourbonJunkie

1/2'' proprotion valve 2 way, AC/DC24V electric modulating valve 0-10V modulating for flow regulation or on/off control @ Aliexpress

grim

That valve looks like a copy of the Belimo

googe

Finally got to try this, works.pretty good!, its fun having control with a button push!. Its a but touchy due to being a ball valve, but seems to work fine, will do more tinkering.

https://www.youtube.com/watch?v=HcPmEKIzSso