Difference between revisions of "Talk:O2k-Peltier Temperature Control"
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Lower ambient temperature does not necessary mean a "cool room". For the 2 deg, an acclimatised room usually will be enough. | Lower ambient temperature does not necessary mean a "cool room". For the 2 deg, an acclimatised room usually will be enough. | ||
WhileĀ we can only guarantee the working of the instrument within theseĀ limits, it is possible to go to 0Ā°C and has been done. In general, thisĀ may require a "cool room". To this purpose the main unit itself can beĀ exposed to temperaturesĀ down to just above 0Ā°C (all the electronicĀ components are rated at least down to 0Ā°C but obviously 0Ā°C roomĀ temperature has to be avoided due to condensation concerns). Also ofĀ course for very low room temperatures above 0 deg humidity has to beĀ controlled somehow. | WhileĀ we can only guarantee the working of the instrument within theseĀ limits, it is possible to go to 0Ā°C and has been done. In general, thisĀ may require a "cool room". To this purpose the main unit itself can beĀ exposed to temperaturesĀ down to just above 0Ā°C (all the electronicĀ components are rated at least down to 0Ā°C but obviously 0Ā°C roomĀ temperature has to be avoided due to condensation concerns). Also ofĀ course for very low room temperatures above 0 deg humidity has to beĀ controlled somehow. | ||
We did a quick test today and could reach 0Ā°CĀ chamber temperature quite easily at a room temperature of about 14 Ā°C.Ā To keep this temperature stable the cooling power of the Peltier elementĀ was already working at 95% of maximum, so some kind of cool room willĀ probable be necessary | We did a quick test today and could reach 0Ā°CĀ chamber temperature quite easily at a room temperature of about 14 Ā°C.Ā To keep this temperature stable the cooling power of the Peltier elementĀ was already working at 95% of maximum, so some kind of cool room willĀ probable be necessary. | ||
Ā | |||
update for O2k Series E: | |||
Because Series E Oxygrahs have a more efficient temperature management system the experiment described above was repeated with a Series E O2k. In this case it was not necessary to reduce the room temperature: | |||
Ā | |||
O2K - 0Ā°C block temp.Ā - stable Peltier power was reached after about 1:05 h from setting blockĀ temp. from stable 37Ā°C to 0Ā°C. - stable Peltier power was about -83 %. - room temperature was 21.1Ā°C | |||
Revision as of 15:03, 4 February 2013
Very low temperatures
Question: Is it possible to use the oxygraph with a chamber temperature of 0 Ā°C?
Our system is specified down to 4 Ā°C at 25 deg room temperature and and down to 2 Ā°C at "lower ambient temperature", see specifications. Lower ambient temperature does not necessary mean a "cool room". For the 2 deg, an acclimatised room usually will be enough. While we can only guarantee the working of the instrument within these limits, it is possible to go to 0Ā°C and has been done. In general, this may require a "cool room". To this purpose the main unit itself can be exposed to temperatures down to just above 0Ā°C (all the electronic components are rated at least down to 0Ā°C but obviously 0Ā°C room temperature has to be avoided due to condensation concerns). Also of course for very low room temperatures above 0 deg humidity has to be controlled somehow. We did a quick test today and could reach 0Ā°C chamber temperature quite easily at a room temperature of about 14 Ā°C. To keep this temperature stable the cooling power of the Peltier element was already working at 95% of maximum, so some kind of cool room will probable be necessary.
update for O2k Series E: Because Series E Oxygrahs have a more efficient temperature management system the experiment described above was repeated with a Series E O2k. In this case it was not necessary to reduce the room temperature:
O2K - 0Ā°C block temp. - stable Peltier power was reached after about 1:05 h from setting block temp. from stable 37Ā°C to 0Ā°C. - stable Peltier power was about -83 %. - room temperature was 21.1Ā°C
