This program is automatically transferred to the PMA2100 upon
connection of the probe yielding immediate readings without the
necessity of configuring the meter. This approach guarantees full
interchangeability of the probes and high degree of traceability. A
number of unit conversion algorithms are also programmed into the
probe simplifying its use.
The relative humidity is the ratio of the actual vapor pressure to
the saturation vapor pressure at the air temperature, expressed in
percent. Relative humidity displays an inverse relationship with
absolute temperature when the vapor pressure is held constant.
The Dewpoint calculating program is also included in the memory
capsule. The Dewpoint is the temperature the air would have if it
were cooled , at constant pressure and water vapor content, until
saturation (or condensation) occurred.
A temperature compensated capacitive sensor is used in the PMA2170
to achieve high accuracy and long term stability over a broad range
of environmental conditions. The sensor exhibits low hysteresis. A
membrane filter and housing protect the sensor from contaminants.
The humidity sensitive capacitive elements for this probe are
manufactured to very tight specifications and factory-calibrated
allowing simple replacement, should the sensor get damaged. No
additional calibration is necessary.
Humidity is a very important factor for the comfort of humans and
animals, operating sensitive electronic equipment, working with high
voltage or static sensitive components. Fabrics, adhesives and paper
change their properties with the ambient humidity. Even some
precision mechanisms might be affected by humidity.
Comfortable room relative humidity at 20-25°C is around 50% RH. It
may vary from 38% RH in class-10 clean rooms to 60% RH in hospital
operating rooms. |