Vaisala HMP42 - Manual (Page 5)

HMI41 AND HMP42
M210317EN-A Operating Manual
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1. THE HMI41 INDICATOR AND PROBES
The HMI41 is an easy-to-use portable humidity and temperature indicator for
a variety of applications, including such as industrial monitoring and
inspections, occupational health and safety, laboratory and research use, spot
checking etc. When equipped with optional calibration cables, the HMI41 can
also be used as a field calibrator for most Vaisala transmitters.
The HMI41 has as many as six different probe types to choose from. The
indicator recognizes the probe type automatically, so there is no need to
change settings each time the probe is changed. However, please, note that this
feature is active only in indicators and probes with letters ID in the instrument
label. For previous versions, the probe type has to be set manually. The
HMP44 is an exception, as indicators marked with ID recognize automatically
all versions of this probe. All probe types are optimized for different
applications:
• HMP41 probe can be used for measuring humidity and temperature in
numerous applications, for example in spot checks.
• HMP42 probe head has a diameter of only 4 mm. The HMP42
consists of a handle a 23.5 cm long probe head. This remarkably small
and round probe structure is specially indicated for measurements in
very tight spaces, e.g. in joint spaces between tiles and in air
conditioning channels, as well as for measuring the equilibrium
humidity of e.g. timber; the operating temperature range is
-40 - +100 °C.
• HMP44 and HMP44L are used for measuring humidity in concrete
and other structures.
• HMP45 probe is indicated for measurements in channels and other
places that are difficult to reach and therefore require a probe head
with cable.
• HMP46 probe is optimized for measurements in relatively high
temperatures (up to +100 °C, temporarily even +180 °C), in dirty
processes and in general in applications that require a robust probe
structure.