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

Printable Version  
Author: Subject: First hotplate
spoofy
Harmless
*




Posts: 7
Registered: 12-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 12-6-2009 at 15:04
First hotplate


I just got my first hotplate which in theory should heat up to 380C. Just to test it I put a 500ML beaker with 400ML of water in it and put it on "5" (the temp knob goes up to 9). Its been roughly 45 minutes and the water has not come to a boil yet.

So my question, do hotplates normally take a very long time to warm up? I'm using the BioMega h4000-HS
View user's profile View All Posts By User
User
Hazard to Others
***




Posts: 339
Registered: 7-11-2008
Location: Earth
Member Is Offline

Mood: Passionate

[*] posted on 12-6-2009 at 15:32


What is the rating if your plate?
I have a couple of plates and one of them also has a hard time reaching high temp.
Low wattage can be the cause.




What a fine day for chemistry this is.
View user's profile View All Posts By User
DJF90
International Hazard
*****




Posts: 2266
Registered: 15-12-2007
Location: At the bench
Member Is Offline

Mood: No Mood

[*] posted on 12-6-2009 at 17:17


You should never fill your flasks that full. 2/3rds maximum. For a 500ml flask, I would expect 150-200 watts to be (more than) adequate.
View user's profile View All Posts By User
spoofy
Harmless
*




Posts: 7
Registered: 12-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 12-6-2009 at 17:38




Speed Range: 60—1500 rpm

Temperature Range: Ambient +5 to 380 C

Platform: 7.5 x 7.5 in.

Control: Quick Adjustment Knobs

Dimensions:8(W) x 9(D) x 4.5(H) in.

Electrical Data: 120V, 60 HZ / 230V, 50/60 HZ












View user's profile View All Posts By User
EmmisonJ
Hazard to Self
**




Posts: 89
Registered: 5-1-2009
Member Is Offline

Mood: No Mood

[*] posted on 19-6-2009 at 09:19


i don't know if that's common for many people or not but mine is the same way with similar specs.

in my personal experience hotplates take a little bit of getting used to, to get a feel for them. ie: get a feel for how quickly it warms up or cools off and what temp you can expect from the dial settings as well as the time it takes to get there, mine does both very slowly. i feel you though, mine is painstakingly slow. maybe should've bought a $1000 hotplate instead of a $350 one. a while back i lost power while maintaining a nice reflux, it took an hour afterwards to dial it back to the right constant temp, overshooting and undershooting the temp until i eventually got it.
View user's profile View All Posts By User
User
Hazard to Others
***




Posts: 339
Registered: 7-11-2008
Location: Earth
Member Is Offline

Mood: Passionate

[*] posted on 20-6-2009 at 02:51


I can confirm this, u indeed get a feel for the dials.
I now that distilling sulfuric acid is not gonna work with one of my plates as it just hasn't got enough surge for it.
This is also an advantage for situations where i don't want to exceed certain temperatures.
This plate is rated 525watts and it just isn't that much.
Another hotplate sitting around is rated 2800watts and i can tell , that's a difference. It turns almost redhot in a matter of seconds.

[Edited on 20-6-2009 by User]




What a fine day for chemistry this is.
View user's profile View All Posts By User
EmmisonJ
Hazard to Self
**




Posts: 89
Registered: 5-1-2009
Member Is Offline

Mood: No Mood

[*] posted on 20-6-2009 at 06:07


Quote: Originally posted by User  
I can confirm this, u This plate is rated 525watts and it just isn't that much.
Another hotplate sitting around is rated 2800watts and i can tell , that's a difference. It turns almost redhot in a matter of seconds.


that is excellent advice for shoppers of hotplates that don't want to spend an hour to reach desired temperatures. perhaps when mine kicks the bucket (it better not for a long time! haha) i'll upgrade to a higher wattage hotplate. will definitely stick with a hotplate, not a big fan of mantles even though they have their benefits, hotplates are more versatile. just my personal preference there

[Edited on 20-6-2009 by EmmisonJ]
View user's profile View All Posts By User
spoofy
Harmless
*




Posts: 7
Registered: 12-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 3-7-2009 at 09:55


update..

first place couldn't boil water .. so i sent it back

second plate took 10 hours to heat 400ml of oil to 200C

I would suggest others avoid this brand if possible.. they are cheap.. but from my experience not useful at all.

[Edited on 3-7-2009 by spoofy]
View user's profile View All Posts By User
entropy51
Gone, but not forgotten
*****




Posts: 1612
Registered: 30-5-2009
Member Is Offline

Mood: Fissile

[*] posted on 3-7-2009 at 11:02


spoofy, it sounds like you accidentally bought the model with training wheels on it :D

Next time try a Corning. I've killed lots of hotplates, but I've had a Corning for 20 years and it refuses to die.




Better to remain silent and appear a fool than to open your mouth and remove all doubt.
View user's profile View All Posts By User
Saerynide
National Hazard
****




Posts: 954
Registered: 17-11-2003
Location: The Void
Member Is Offline

Mood: Ionic

[*] posted on 4-7-2009 at 08:48


When mine arrived in the mail, the first thing I did was set it on the counter and cook lunch (pasta).

I was disappointed to find the stove was much better at accomplishing this task (30 min and the pasta is still only half cooked!). However, it works fine for chemistry, so thats a relief :D.

[Edited on 7/4/2009 by Saerynide]




"Microsoft reserves the right at all times to monitor communications on the Service and disclose any information Microsoft deems necessary to... satisfy any applicable law, regulation or legal process"
View user's profile View All Posts By User
EmmisonJ
Hazard to Self
**




Posts: 89
Registered: 5-1-2009
Member Is Offline

Mood: No Mood

[*] posted on 7-7-2009 at 06:37


i'm in the same boat spoofy, live and learn.

i've had mine for only a year, it is a different brand but the specs are the same as yours so it's either comparable or is the same thing but re-branded.

if one can save up the money for a real brand, they do pay for themselves eventually.
View user's profile View All Posts By User
UnintentionalChaos
International Hazard
*****




Posts: 1454
Registered: 9-12-2006
Location: Mars
Member Is Offline

Mood: Nucleophilic

[*] posted on 7-7-2009 at 06:41


I'm not sure what models everyone uses, but one that crops up a lot is a Corning PC-351. I have one and it works very nicely. I snagged it on ebay for about $120 although I'm under the impression that this was very cheap.

[Edited on 7-7-09 by UnintentionalChaos]




Department of Redundancy Department - Now with paperwork!

'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
View user's profile View All Posts By User
User
Hazard to Others
***




Posts: 339
Registered: 7-11-2008
Location: Earth
Member Is Offline

Mood: Passionate

[*] posted on 7-7-2009 at 06:44


If you just need brute force without stirring one could buy a second hand electric cooking plate.these things often don't cost shit and i have seen them going well over 2000watts.
I have one which i use often to just heat things quickly.
for example to boil down battery acid it is very useful.
Nothing special, just brute force and cost next to nothing.




What a fine day for chemistry this is.
View user's profile View All Posts By User
Phosphor-ing
Hazard to Others
***




Posts: 244
Registered: 31-5-2006
Location: Deep South, USA
Member Is Offline

Mood: Inquisitive

[*] posted on 7-7-2009 at 11:09


You have to be aware that those cheap electric burner/cooking plate things are not sparkless. Using them to heat flammables could be hazardous to your health.



"The nine most terrifying words in the English language are: 'I'm from the government and I'm here to help.'" -Ronald Reagan
View user's profile View All Posts By User

  Go To Top