Vaisala CARBOCAP GMP231, Руководство пользователя, Страница: 19 / 92

3. Installation
3.1 Thermal management
GMP231 is designed to remain installed during typical heat sterilization cycles that raise the
chamber temperature to 180 °C (356 °F). Since 180 °C is the target temperature for
sterilization, it is likely that there are hotspots inside the chamber that are above this
temperature. Avoid installing the GMP231 near such hotspots, for example near heating
elements. Do not expose the GMP231 to temperatures higher than 195 °C / 383 °F.
The following considerations are most important for achieving the specified heat durability
and measurement stability:
• Only the sensor and its filter should be exposed to heat. The filter must be completely in
the heated chamber. The probe body must remain inside the unheated chamber wall so
that only the end of the probe body extends exactly 2.5 mm into the chamber.
• During the sterilization cycle, you must set the GMP231 to standby mode (turns off the
CO
2
measurement), or power off the probe completely. The GMP231 automatically stops
its measurement cycle if it detects a high temperature, but it is best if the incubator’s
control system sets the GMP231 to standby mode when the sterilization cycle is started.
• The installation tube must be sealed from the chamber side to limit heat conduction, and
to prevent CO
2
in the chamber from entering the probe. Vaisala recommends a 44 mm
diameter installation tube together with Vaisala’s silicone plug.
• If the chamber wall contains heating elements, or has a construction where hot air is
circulated inside the wall, design the installation tube so that excessive heat is not
conducted to the GMP231.
3.2 Avoiding condensation
The sensor head of the GMP231 is heated during normal operation, which prevents
condensation from forming inside the filter and on the optical surfaces. The heating is not on
when GMP231 is in standby mode or unpowered. For this reason, keep the probe powered and
operating when the incubator is in use and humidity inside the chamber is high.
Correct installation depth of the probe is also important for preventing condensation from
running to the sensor along the chamber wall.
3.3 Probe installation depth
GMP231 must be installed so that only the sensor element and the filter are inside the chamber.
If the probe is longer than the installation tube, the extra length should extend to the outside
of the chamber.
The installation depth must be 2.5 mm. This installation depth provides the specified heat
durability of the probe, and allows the silicone plug to seal the Ø 44 mm installation tube
properly.
Chapter 3 – Installation
17