Sciencemadness Discussion Board

Swap the aluminium and ceramic top plates of two hotplates

Cendre - 3-8-2024 at 23:47

Hey, I know this is not exactly the right forum for this but it’s the closest. Is it possible to swap the plate (top) of a hotplate for a different one? I.e. swapping the ceramic and aluminium plate of two hotplates that are the same model? Or will it damage some internals, maybe because it will change the power draw or similar?
The two plates I might to this to have similar specs, however one is digital and one analogical (non digital). But that shouldn’t be any different for the plate but I might be wrong. Has anyone attempted that before?
My goal is to transfer my ceramic plate on my digital hotplate instead of it’s current aluminium one.
The two models are the DM300 (digital, aluminium, 370C) and EC300 (analog, ceramic, 420C).
I will only have access to the two units in a week, and I will check the heating elements as I don’t know if they are different as they are rated for different temperatures, but maybe that is because of the top plate and the digital one when swapped for a ceramic top might be able to also reach 420C.


[Edited on 4-8-2024 by Cendre]

IMG_6859.jpeg - 734kB

Sulaiman - 4-8-2024 at 05:10

It looks like analog/digital and ceramic/metal options are interchangeable, (at time of manufacture)
But, before disassembling anything:

Check if the digital temperature can be set to your required maximum,
If not then you would need to change the max temp limit variable,
I don't know how or if possible.
It is possible that the controller can detect which plate is fitted, but I doubt it.
(Look for any difference in the wiring and connectors of the two heaters)
If you are lucky there could be labeled jumpers on the PCB.

Internal wiring is often crimped or welded rather than soldered,due to material incompatibility and high temperatures.
If just nuts/bolts/screws then ok, but check first.

It could be an extremely simple procedure,
or a nightmare that you will wish you'd never started.

Cendre - 7-8-2024 at 09:31

The aluminium digital one is first, the ceramic analog one is second. The digital one rated for 1430W has way more components (several motors and heating resistances) than the analog ceramic one rated for 2500W.
It doesn’t seem like either has a variable to adjust max temperature.
Edit: it looks like the digital one has 4 separate sets of motor + heater which work on each corner of the machine
IMG_6923.jpeg - 2.6MB IMG_6924.jpeg - 2.3MB

[Edited on 7-8-2024 by Cendre]

[Edited on 7-8-2024 by Cendre]

Nightmare !

Sulaiman - 7-8-2024 at 10:52

I would not consider any swapping around.
Keep two working units.
(I assume you've already reached this conclusion.)

macckone - 10-8-2024 at 16:43

Given the power difference between the two heating elements, I am going to say incompatible. The mosfet and/or triacs used in the digital version are probably not going to handle the additional power. If you can switch the actual top, in most hot plates the heating element is removable from the top plate, you could go that route. But most high temp reactions don't require more precision that the analog plate provides ie. +- 5 or 10C.

I would keep them as is. The aluminum plate on the digital plate is going to provide better accuracy than ceramic.

Deathunter88 - 10-8-2024 at 19:47

Quote: Originally posted by macckone  
Given the power difference between the two heating elements, I am going to say incompatible. The mosfet and/or triacs used in the digital version are probably not going to handle the additional power. If you can switch the actual top, in most hot plates the heating element is removable from the top plate, you could go that route. But most high temp reactions don't require more precision that the analog plate provides ie. +- 5 or 10C.

I would keep them as is. The aluminum plate on the digital plate is going to provide better accuracy than ceramic.


Good advice. I will add a small caveat (since I enjoy browsing hotplate stirrer spec sheets) that almost all ceramic hotplates I've seen have a more accurate temperature accuracy compared to ceramic (usually +/- 5C instead of 10C for aluminum).

macckone - 11-8-2024 at 17:44

Using a device with a top it isn't configured for is going to reduce accuracy.
Most of the aluminum tops provide better conductivity. But yeah there is a lot of variation. Most of which is determined with rather they use a Platinum RTD vs Thermocouple. Thermocouples are pretty inaccurate. A lot of analog models use a comparison between a resistor setting and a thermocouple output. While most decent digital use a Platinum RTD. Of course there are also analog ones that just use a variable resistor and diac/triac setup that don't actually measure temperature.