How to limit the heating of a 5V heating pad (easy way)

Help & Support Robot Parts
1

Hello!

I’ve just bought this pad -> pad
I was hoping that behind the technical specification of the thermal flow “Obtenez un toucher chaud, mais pas trop” (“get a warm touch, but not to much”) I would have something I could work with. But it heats too much.

Is there a way to get 30% of the thermal flow only? I saw I would have to play with the voltage but I do not not exactly how… a potentiometer maybe? What would you suggest to be able to easily get the heating down (or to be able to tune it if it is possible).

Thanks a lot for your answers! I wanted to contact the technical support of the website directly but here I am… sorry about the “first post and asking a lot” kinda thing.

All the best,

zat

2

Hi,

The way we see to reduce the thermal flow of the pad is probably, like you mentioned, reduce the voltage applied to it.
The manufacturer doesn’t mention the operating voltage range of the pad. Therefore, you can add a potentiometer to vary the voltage applied to, let’s say 3V ~ 4.5V.

Cheers,

3

Thanks a lot for your answer!

So I just have to put a potentiometer between the + of the power and the red wire of the pad? I do not know anything about the electrical resistance of the pad so which potentiometer would you advise to me in order achieve a range of 3V ~4.5V? (value, kind, maybe a link?)

Oh, btw! My power source can output 3.3V, can I try this voltage for testing without harming the pad?

Thanks for your patience and your answers, I am learning electronics here… =)

4

Hi,

You can try to apply 3.3V to the pad and see if the temperature obtained is correct. As long as you don’t go over the rated voltage, which is 5V, it shouldn’t harm the pad.
To confirm this, we have contacted the manufacturer to ask them about the voltage range of this pad and if it’s possible to reduce the voltage in order to reduce the temperature.
They might reply directly here. If not, we will post their answer here.

Cheers,

5

Thanks for your answer again. I will make my tests then and I look forward to their answer. BTW you will have the result of the tests there.

Cheers =)

6

Hi,

Here is what the manufacturer says about the heating pad :

Hope this helps,

7

Thanks a lot! Now I am sure about the voltage range =)

Finally I will go PWM with an ESP… it’s gonna be way easier…

For the record, here is how it is gonna be done:

  • I will provide a power source of 5v
  • The pad will be connected to it through a N-Channel MOSFET
  • The ESP will control the N-Channel MOSFET with a dedicated program
  • The ESP will be powered by 3.3V
  • A potentiometer will be connected to the ESP

About the program, I will find the maximum heat I want to produce, and the associated voltage. This is gonna be my threshold. Then I will enable, through a potentiometer, the user to tune the voltage between 0V and the given threshold.

Thanks for all the advices! And do not hesitate to go and get a look at my website (full of those kinda stuff =) )
-> bastienbonard.org/?page_id=1815 (project section is quite fine too)

8

Hi,

Really nice projects your got on your blog. Thank you for posting your solution on the forum.

Regards,

9

Thanks!

At your service :wink: