Data Harvest EASYSENSE Q3+, Руководство пользователя, Страница: 30 / 40

EASY
SENSE Q3+ and Q5+ DO185 (2)
Practical information for the plug-in Temperature sensor
•
It is the tip of the sensor that is sensitive to temperature.
•
Lay the sensor on its side, not its end, when measuring a surface temperature.
•
Temperatures higher than 150ºC may damage the sensor.
•
The PVC insulation on the connecting cable has a working range of -10 to 85ºC, so
keep this cable away from the source of heat e.g. by clamping the sensor in position.
•
Do NOT put any part of the sensor in a direct flame or on a hot plate.
•
Avoid submerging the sensor beyond the stainless steel portion.
•
Wash the sensor thoroughly after use.
•
The boiling point of water will vary with changes in air pressure. At one atmosphere of
pressure (101.3kPa, 1013mBar) pure water boils at 100ºC. Water boils when the
vapour pressure of water equals the pressure of the gases above water, so if the
pressure changes, then the temperature that the water boils at will also change.
Boiling Point of Water vs. Pressure
Pressure in kPA Pressure in mBar Temperature in ºC
101.3 1013
100.0
99.5 995 99.5
97.8 978 99.0
96.0 960 98.5
94.4 944 98.0
92.7 927 97.5
•
AISI 316 stainless steel has a high resistance to corrosion from a wide variety of weak
acids and alkalis. Some environments e.g. saltwater may cause some discolouration to
the stainless steel tube but this will have no effect on the sensor’s performance.
•
The sensor can be left in an alkaline solution such as Sodium Hydroxide (NaOH) for
up to 48 hours, with only minor discoloration. We do not recommend use in a solution
whose concentration is greater than 3 mol dm
-3
.
•
The maximum length of time recommended for exposure to an acid is dependent on
the acid’s concentration. In general, we do not recommend that temperature sensors be
left to soak in acids of between 1 – 3 mol dm
-3
concentrations for longer than 48 hours.
The exceptions to this rule are Hydrochloric acid (HCl), and Sulphuric Acid (H
2
SO
4
).
The maximum recommended times for exposure are:
Concentration of
hydrochloric acid Maximum
exposure
1 mol dm
-3
20 minutes
2 mol dm
-3
10 minutes
3 mol dm
-3
5 minutes
Concentration of
sulphuric acid
Maximum
exposure
1 mol dm
-3
48 hours
2 mol dm
-3
20 minutes
3 mol dm
-3
10 minutes
Suggested Investigations:
Monitoring indoor and outdoor temperature. Weather studies. Insulation studies.
Monitoring endothermic and exothermic reactions. Solubility of salts. Studying freezing
and boiling points. Cooling rates. Evaporation, radiation, conduction and convection
investigations.
©
Data Harvest Group Ltd.
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