Well... the labels were ready to pick up today.
A flaw occurred in the printing.
The word "controller" somehow picked up a space between the E and the R.
They gifted me this 3000 labels and will reprint my order after the upcoming National Day holiday.
I would have wished red instead of blue, for a better association with the new SD logos. Blue is so cold, whereas red >> hot >> fire >> Dragon >> StillDragon B-)
StillDragon Europe - Your StillDragon® Distributor for Europe & the surrounding area
@Prairiepiss said:
I would love to find a 10 turn pot. That could be used. I've looked numerous times. With no luck.
PP try Newark (element14) stock a 10 turn pot in 300K or 500K Potentiometers at 5W. These are larger than your standard pot at 2" deep & 1.8"diameter, but retail for $65US.
If you are looking at buying one from them, use their "quote" service. You may get a good discount. I previously bought a steel enclosure through their "quote" system and received a $150 discount (it retailed for over $300)!
I can put about 400 of the dial stickers in a large express envelope and send that to Larry in a few days. Today begins the National Day holiday here and it is best for me to not go outside for a couple of days. It gets a little hectic here during holidays as you can see at this train station today...
It is personal choice. I am building a 9kW controller at the moment using a PSR-40 module with heatsink and fan cooling in an IP66 wall box. Add in 3 core 4 mm square cable, and the cost is a lot higher than $65. The PSR-40 alone costs more than that.
No right or wrong answers - just different ways to do things. :)>-
If I built a 9 or 11kw controller, I would just have it be for two elements and use a small switch and a 30A contactor switch for one 4500-5500W element and the DIY controller for the other... heck, I know breweries that have 3 6KW elements in a 90 gallon kettle, I built them a variable dongle for one of the elements, they find it easier to just use 3 elements on full power to heat, and 2 elements to boil once it is there...
Just a quick question regarding the 2w 500k pot. Why do you connect pins 1 and 2 together when control can be achieved with connections to just 2 and 3?
Ok, Why Three Lugs?
The most confusing thing to me about pots was that it had three lugs. Why? I mean a resistor only has two connections, shouldn’t a variable resistor also have just too connections? Well sure, and there are variable resistors (called rheostats) that only have two connections. But if you add a third lug, the humble rheostat becomes the mighty potentiometer.
As you turn the shaft, the resistance between the wiper and lugs 1 and 3 changes inversely. For example, if you turn the shaft clockwise, the resistance between 1 & 2 increases while the resistance between 2 and 3 decreases.
So if you think about it, the resistance between lugs 1 and 3 never changes. If you have a 100k pot, the resistance between 1 and 3 will always be 100k no matter how you turn the knob. It is the wiper (lug 2) that changes.
All good reading here, very informative as to how to wire the controller up and why it is done so.
I have a question regarding power output, or rather, knowing exactly how many watts the heater is using in relation to where the potentiometer knob is set to. How can I tell?
I will running a single 5500w heating element, full power to heat up and then controlled down for refluxing. How will I know when I have the pot set to give me 1000w, or 850w?
@captainshooch said:
You can also get a volt/amp meter like I have for 19.00 +/- like this one good from 80-300 volts and super easy to install/wire up
Comments
I stock 2w 470K ohm as the SSR manufacturer suggests on page 2 of this thread.
This seems to work well with 220~240 volts but do you need a different pot if controlling a 110~120 volt element?
Mosca this one is 500k and cheaper too
A500K OHM 2W Audio Tape Round Shaft Potentiometer 2PCS
Interesting info on pots
The Secret Life of Pots
Thanks guys, I was looking at that model because of the counting dial. With a 10 turn it would give me a very precise heat regulation.
M-
Well... the labels were ready to pick up today.
A flaw occurred in the printing.
The word "controller" somehow picked up a space between the E and the R.
They gifted me this 3000 labels and will reprint my order after the upcoming National Day holiday.
Even with the small flaw, they still look good to me!
I would have wished red instead of blue, for a better association with the new SD logos. Blue is so cold, whereas red >> hot >> fire >> Dragon >> StillDragon B-)
StillDragon Europe - Your StillDragon® Distributor for Europe & the surrounding area
@moscca awesome find! 10 turn pot @ 2W !
https://www.youtube.com/watch?v=ty6eY9VUIgI
Yes, buy t is only rated 100K and I saw now that we need 470K according the SSR.
you could always wire 6 of them in series! =))
https://www.youtube.com/watch?v=ty6eY9VUIgI
I would love to find a 10 turn pot. That could be used. I've looked numerous times. With no luck.
PP try Newark (element14) stock a 10 turn pot in 300K or 500K Potentiometers at 5W. These are larger than your standard pot at 2" deep & 1.8"diameter, but retail for $65US.
If you are looking at buying one from them, use their "quote" service. You may get a good discount. I previously bought a steel enclosure through their "quote" system and received a $150 discount (it retailed for over $300)!
not affiliated, but a happy customer :D
Has anyone used a PWM as an alternative?
@Lloyd, how do I get a Couple of those sticker ? I don't have any still dragon stickers and I order all my stuff exclusively from SD
I'll send controller stickers to each distributor on their next order. It may take awhile.
I can put about 400 of the dial stickers in a large express envelope and send that to Larry in a few days. Today begins the National Day holiday here and it is best for me to not go outside for a couple of days. It gets a little hectic here during holidays as you can see at this train station today...
@olddog yes I have build a PWM based controller. my control panel has a 3 way switch on it, pos 1 for PWM, pos 2 for PWM & pos 3 for 100%.
I based this build on Swede's documented controller build on artisan. I have posted my circuit diagram there too.
I use one as well, and like @crozdog, also based mine on Swede's build.
@Philter, $65 ugh. I could buy a PID for that. That's ridiculous.
It is personal choice. I am building a 9kW controller at the moment using a PSR-40 module with heatsink and fan cooling in an IP66 wall box. Add in 3 core 4 mm square cable, and the cost is a lot higher than $65. The PSR-40 alone costs more than that.
No right or wrong answers - just different ways to do things. :)>-
If I built a 9 or 11kw controller, I would just have it be for two elements and use a small switch and a 30A contactor switch for one 4500-5500W element and the DIY controller for the other... heck, I know breweries that have 3 6KW elements in a 90 gallon kettle, I built them a variable dongle for one of the elements, they find it easier to just use 3 elements on full power to heat, and 2 elements to boil once it is there...
definitely a bypass switch for full power 9kw is a lot of power
https://www.youtube.com/watch?v=ty6eY9VUIgI
Just a quick question regarding the 2w 500k pot. Why do you connect pins 1 and 2 together when control can be achieved with connections to just 2 and 3?
OD
Ok, Why Three Lugs?
The most confusing thing to me about pots was that it had three lugs. Why? I mean a resistor only has two connections, shouldn’t a variable resistor also have just too connections? Well sure, and there are variable resistors (called rheostats) that only have two connections. But if you add a third lug, the humble rheostat becomes the mighty potentiometer.
As you turn the shaft, the resistance between the wiper and lugs 1 and 3 changes inversely. For example, if you turn the shaft clockwise, the resistance between 1 & 2 increases while the resistance between 2 and 3 decreases.
So if you think about it, the resistance between lugs 1 and 3 never changes. If you have a 100k pot, the resistance between 1 and 3 will always be 100k no matter how you turn the knob. It is the wiper (lug 2) that changes.
from: Resistors and Potentiometers: A Practical Guide
https://www.youtube.com/watch?v=ty6eY9VUIgI
Also if the wiper (variable part of the pot) decides to go open circuit, you have a failsafe of high resistance between 1 & 3.
All good reading here, very informative as to how to wire the controller up and why it is done so.
I have a question regarding power output, or rather, knowing exactly how many watts the heater is using in relation to where the potentiometer knob is set to. How can I tell?
I will running a single 5500w heating element, full power to heat up and then controlled down for refluxing. How will I know when I have the pot set to give me 1000w, or 850w?
Thanks.
Get your self an amp probe and meter the line connected to the SSR
StillDragon North America - Your StillDragon® Distributor for North America
You can also get a volt/amp meter like I have for 19.00 +/- like this one good from 80-300 volts and super easy to install/wire up
AC 80V- 300V/ 100A Volt Amp LED Meter Voltammeter With Current Transformer USA
Very Nice! "Bling on a budget"
Good find,CH, bought one.