PID controller help

Help Support and Requests
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225

Welll…then we MIGHT get into “problems with your switch…”, except they may be “problems with your switching power supply”.

As in “don’t add more watts than you gots”…

A) the 12V supply you purchased has a power limit.

B) The pads you purchased have power requirements (they’ll just take that shit!). If A is not larger than B you’ve got problems.

So check the specs and do some math before adding more 12V load to your “switcher”.

Edit: if you purchased a1A 12V power supply. You can run a nominal 12W of heating pads

Power = Voltage x Current

12W = 12V x 1A

Or if you’re now looking for a bigger 12V power supply… P/V = Current (amps required)

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226

Got it working with the help of @DillyFWonka

Apparently all I had to do was switch around a few wires then take the wires from my AC/DC and properly wire those to my heat pads

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227

So uh only “issue” so far is the fact it wont go up to 120F only to like 86-95

Connected 2 more heat pads and still barely going up. My current AC/DC is 1.25-2 amps, should I buy a 5 amp?

228

what are the specs on your heating pads?

more power is usually a good thing…but figuring out how much you need requires understanding what you’ve got already.

so how many watts of heating pad have you hooked up?
in series or parallel?

how about a picture. because 1.25-2A just doesn’t sound right (rating as a range doesn’t jive).

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229

https://www.amazon.com/12V-Flexible-Polyimide-Heater-Plate/dp/B076PD7TXW/ref=mp_s_a_1_22?dchild=1&keywords=heat+strips&qid=1627312132&sr=8-22

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These ones

230

And how many…?

A 1A supply is enough for a SINGLE heat strip drawing 12W

If you’ve got two 12W and two 7W strips, you’re trying to draw 38W/12V = how many amps?

To which your power supply should probably respond with “fuck you buddy!” (Rather than just catching fire…)

Edit: which reminds me I have to go have a very firm chat with a VFD that believes it’s acceptable to draw 61A from its 50A breaker to achieve the same goals as its buddies manage with 40A. I can nay get the power Captain!

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231

4 of the smaller ones and 2 of the wider ones

232

Do the math… how big a power supply do you need? (No 5A won’t cut it…)

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233

The next question is: what makes you think that controlling six different zones using one temperature reading and controller is going to bring you solid thermoregulation?

On/off will be set by whichever heating pad warms the probe. But that has little bearing on how warm the other pads have managed to get their corner of the whirled.

Also matters if you’ve got them in series or parallel

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234

Should I buy one or 2 big heat pads to wrap around instead of multiple ones?

235

Depends on your goal. If you don’t have 6 zones, then 6 heating pads doesn’t seem like the place to start.

https://forums.adafruit.com/viewtopic.php?f=8&t=87463

Maybe see how one 12W pad works (regulates)

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236

Im just stuck and confused. Idk why the fuck its not doing anything at all, everything is plugged in and working just not heating up to what I set it at and I’m getting frustrated more and more at this bullshit.

Just buy a new heat pad that covers the whole gun?

As I’ve put my TC in multiple different spots and still isn’t going up. Just stays at 88-90 then when i take it off it drops.

237

No. Hook up just ONE of the pads you have. Prove you’ve built the right thing.

THEN get a bigger power supply, and add more or bigger heat pads.

You’ve established that using 6 pads, but supplying fuck all in the way of power only works slightly better than one pad and no power at all.

Start by establishing that you built a device that can regulate temp. THEN upsize it to control your process…

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238

No, it fucking doesn’t!!!

Wire up just ONE heat pad. Put your hand on it and the probe between. Remove the probe.

Temp on display drops . Temp on pad stays the same or CLIMBS!!!

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239

I’ve properly built it yes. Me and @DillyFWonka confirmed that last night. The PID itself works.

I’m too new to electrical work to understand how to find the issue/identify it.

I’m just confused on what exactly I have to do/what the issue is, is it the heat pads or the PID? Im going to unplug all the wire and go from there the heat wires

240

Meaning what exactly?

That you could get a single pad 120C and holding?

So where is the confusion?

You’ve got how many watts of heating pad?

How big a power supply do you need?

Watts/12 = Amps needed to make it go.

If it is a single reservoir, then sticking 6 pads on it might work. If you’ve got multiple zones with different needs (reservoir vs feed tube) then using more than one pid makes sense.

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241

Its 7W a pad for the small ones and big ones I believe

I think per pad, i have no clue tho

242

If you confirmed you built it right….

Then you KNOW the only issue is you are not providing the required Electrickery for the herd of heat mats you’ve attached.

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243

So its the AC/DC and heat pads, i will need either less heat pads or a stronger AC/DC?

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244

Is this thing on?!?

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