Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Hotplate continuing to emanate heat despite being unplugged?? (The Phantom Hotplate?)
SoundClown
Harmless
*




Posts: 17
Registered: 17-12-2018
Location: Narnia, USA
Member Is Offline

Mood: Hungry Like the Wolf

[*] posted on 12-12-2020 at 01:18
Hotplate continuing to emanate heat despite being unplugged?? (The Phantom Hotplate?)


Hello all. A few months ago I acquired a Thermolyne Type 1900 hot plate (Model HP-A1915B/Hotplate ONLY) and upon testing it's functionality with a thermometer gun, I discovered an issue. This is the first laboratory based heating device I have ever encountered that CONTINUES to produce heat despite being UNPLUGGED?? I apologize if this isn't the correct posting place but this just really freaked me out lol would there be any type of explanation to this? After unplugging, I point my thermogun to the center of the plate and record temps INCREASING. It's not uncontrollably exceeding in nature and I'm able to cool it down with a water bath and subtle knob adjustments, but the device is UNPLUGGED at this point and should have ceased to circulate any form of energy. Thoughts / explanations? I can post photos and what not if need be

s-l140.jpg - 4kB
View user's profile View All Posts By User
HydrogenSulphate
Harmless
*




Posts: 34
Registered: 13-10-2019
Member Is Offline

Mood: Caffeinated

[*] posted on 12-12-2020 at 01:30


Quote: Originally posted by SoundClown  
Hello all. A few months ago I acquired a Thermolyne Type 1900 hot plate (Model HP-A1915B/Hotplate ONLY) and upon testing it's functionality with a thermometer gun, I discovered an issue. This is the first laboratory based heating device I have ever encountered that CONTINUES to produce heat despite being UNPLUGGED?? I apologize if this isn't the correct posting place but this just really freaked me out lol would there be any type of explanation to this? After unplugging, I point my thermogun to the center of the plate and record temps INCREASING. It's not uncontrollably exceeding in nature and I'm able to cool it down with a water bath and subtle knob adjustments, but the device is UNPLUGGED at this point and should have ceased to circulate any form of energy. Thoughts / explanations? I can post photos and what not if need be


Not powered by uranium, is it? :D Unusual to say the least, but some do take a seemingly long time to cool down.
View user's profile View All Posts By User
Fulmen
International Hazard
*****




Posts: 1646
Registered: 24-9-2005
Member Is Offline

Mood: Bored

[*] posted on 12-12-2020 at 01:45


It's called thermal conductivity.



We're not banging rocks together here. We know how to put a man back together.
View user's profile View All Posts By User
Fyndium
International Hazard
*****




Posts: 1187
Registered: 12-7-2020
Location: Not in USA
Member Is Offline


[*] posted on 12-12-2020 at 02:10


Thermal mass and stuff like that. My hotplate takes a good hour to settle. Issue when you don't need no more heating but gotta keep stirring. Hence I got separate stirrers to switch for.

CaCl2 salt heating baths easily keep their heat to the next day, if they are small like 1-2 liters. Larger ones much longer than that.
View user's profile View All Posts By User
Vomaturge
National Hazard
****




Posts: 283
Registered: 21-1-2018
Member Is Offline

Mood: thermodynamic

[*] posted on 12-12-2020 at 13:19


When it's powered, the elements and the interior of the metal plate are hotter than the surface which is losing heat to whatever you're heating. If you kill the power and remove whatever container you were heating, that heatsink is removed, and the heat from the interior will keep diffusing to the outside. You may have a brief rise in temperature before the whole device has cooled off.



I now have a YouTube channel. So far just electronics and basic High Voltage experimentation, but I'll hopefully have some chemistry videos soon.
View user's profile View All Posts By User
MidLifeChemist
Hazard to Others
***




Posts: 188
Registered: 4-7-2019
Location: West Coast USA
Member Is Offline

Mood: precipitatory

[*] posted on 12-12-2020 at 14:17


yes, that's normal
View user's profile View All Posts By User
SoundClown
Harmless
*




Posts: 17
Registered: 17-12-2018
Location: Narnia, USA
Member Is Offline

Mood: Hungry Like the Wolf

[*] posted on 12-12-2020 at 20:47


Thank you for the feedback everyone! Much love <3 Again I've worked with everything from corning PC's to cheaply assembled heating mantles and never have I observed surface temperature increases upon outlet disconnection. 45 degrees celsius @ 5 min... disconnect.... temp reads ~60 degrees 10 mins later? I suspect the aluminum surface may play a role in the prolonged heating
View user's profile View All Posts By User

  Go To Top