Cavatica - 13-2-2015 at 04:56
Hi guys, I was looking at this hot plate magnetic stirrer (looking to purchase one), and it says in the manual that the temperature probe must be
connected and submerged in the liquid in order for the hot plate to work. This strikes me as weird, as unless you are simply boiling a solution in an
open beaker, you would need a boiling flask with a side arm for the probe, which would increase the risk of leakage and contamination. Then again, I'm
new to these stirrer units, and have no idea whether this is commonplace, and you just go with the side-arm solution, or if there is som kind of
work-around that everyone knows about. I would be grateful for any feedback on this potentially stupid question!
CHRIS25 - 13-2-2015 at 05:14
Don't buy it. This set up is the most ridiculous of all apparatus ever designed, trust me.
Cavatica - 13-2-2015 at 05:18
Thanks CHRIS25, good call!
Btw, any suggestions as to a good stirrer/hot plate?
[Edited on 13-2-2015 by Cavatica]
gdflp - 13-2-2015 at 10:08
Depends on your budget, but I would go for a used name brand rather than a new Chinese one. IKA, Corning, Fischer Scientific, and VWR are all good
brands. Personally, I have a 10in.x10in. Fischer Isotemp that works great as my main hot plate, but it was expensive at around $250USD. I also have
a rather "used" Corning PC-351 and Thermolyne Nuova II that I use when I need more than one for an experimental setup. All of them work fine, but I
find the Nuova II to be a little weaker during both heating and stirring. I love the PC-351, the previous owner just didn't show as much TLC so it's
a little beaten up.
Bert - 13-2-2015 at 10:25
I have a Bibby quartz halogen stir/hot plate. It cost about $240.00 new over 10 years back, and I have never regretted buying. Quartz halogen heat
lamp is quick responding, prefer it for quick changes in heating (kind of like difference between cooking with an electric or a gas range!).
Has a plug in back for using a PID or other temperature control-
http://www.triadsci.com/?site=preowned&item=4583&men...
[Edited on 13-2-2015 by Bert]
Zombie - 13-2-2015 at 17:30
Am I correct in assuming the PID can control the temp of the plate?
In essence bypassing the surface Temp. sensor, and using the PID / thermocouple as the primary Temp. control.
[Edited on 14-2-2015 by Zombie]
Bert - 13-2-2015 at 22:53
PID (and possibly a high current relay) can cycle the heat on and off, you place the thermocouple at whatever part of your apparatus you wish to
control (water bath, still head, reaction mixture) and the PID learns response time of system, anticipates when to switch heating on/off.
http://castboolits.gunloads.com/showthread.php?181319-Pid-Co...
Zombie - 13-2-2015 at 23:01
I have several PID's set up on different projects. I'm a HUGE fan of "fuzzy logic". (probably already guessed that).
I was just curious as to why the plate would have a PID in/out? vs a built in thermocouple port.
Either way I love the quartz plate idea. It's one I have not come across till now.
Cavatica - 14-2-2015 at 08:36
Great, guys, thanks a lot for the input!