Specifications

57
HMM 210 Series Humidity, Dewpoint and
Temperature Modules for Demanding
Applications
DIFFERENT CONFIGURATIONS TO MEET
DEMANDING APPLICATIONS
The HMM 210 series modules are designed for
Original Equipment Manufacturers (OEMs) needing
humidity and dewpoint measurements in demanding
applications. Examples include manufacturers of
environmental chambers, growth chambers, incuba-
tors, and hatchers. These modules provide high
accuracy over wide temperature and relative humid-
ity ranges. Also, they remain accurate and reliable
under extreme conditions where a combination of
high humidity and rapidly changing temperature can
result in condensation on the sensor head.
THREE PROBE CONFIGURATIONS
 RH + T probe
 Dewpoint probe features Vaisalas unique Compos-
ite Sensor, which remains heated a few degrees
above ambient to prevent dew formation (conden-
sation) on the sensor.
 Dewpoint probe described above, together with a
temperature probe for obtaining dewpoint, relative
humidity, and temperature outputs
THREE BOARD CONFIGURATIONS
 HMM 211 has analog outputs, and three-wire
design. It is compatible with all three probes
 HMM 212 has current outputs, and two-wire
design. It is compatible only with the RH + T
probe.
 HMM 213 has RS232 output, and is compatible
with all three probes
DIFFERENT PROBE AND CABLE LENGTHS
AVAILABLE
 The probes are 12 mm in diameter and available in
lengths of 90* or 215 mm.
 Cable lengths of 65 cm, 150 cm or 300 cm are
available for the RH+T and dewpoint probes
 Cable lengths of 150 cm or 300 cm available for the
temperature probe
*Humidity probe warming only available for the
90 mm probe.
UNIQUE COMPOSITE SENSOR DESIGN
OFFERS SEVERAL ADVANTAGES
This Composite Sensor, available on the dewpoint
probe configuration, is warmed to always remain a
few degrees higher than ambient. Advantages of this
patented technique include:
 No condensation problems on the sensor, as the
temperature of the probe always remains higher
than the ambient
 Fast response time, especially in rapidly changing
temperatures
 Improved stability and accuracy in high humidities
NEW RE-GAINING OPTION
For 25 years, Vaisalas HUMICAP sensor has proven
its resistance to dust and most chemicals, time and
time again. However, for some extreme applications
such as chemical exposure in chambers, when there
is a risk of certain rare chemicals accumulating on the
sensor, thereby decreasing accuracy, Vaisalas new
re-gaining option is recommended. With this option,
contaminants are evaporated from the sensor and
performance is returned to normal. Re-gaining is
always activated when the module is switched on to
remove the effects of cleaning, sterilization, etc.
HMM 211 shown
with dewpoint probe