SABLE SYSTEMS INTERNATIONAL
RH - 300 DewPoint /Relative Humidity Meter
Sable Systems’ high-resolution RH-300 is a compact, flow-through meter for dewpoint, relative
humidity, water vapor pressure and water vapor density analysis. It has analog outputs,
built-in calibration and diagnostics, and direct data-logging capability into any computer.
Consider the RH-300:
 High resolution. 0.001% RH, 0.001°C cell temperature, 0.01°C
dew point, and 0.01 - 1 Pa water vapor pressure; 0.001 – 0.1 μg
ml-1 water vapor density.
 Flow through design. The RH-300 is specifically designed for
flow-through use.
 Versatility. Most instruments measure only relative humidity or
dew point. The RH-300 measures both, plus water vapor pressure
and water vapor density.
 Accuracy. 1% accuracy for relative humidity, water vapor
pressure or water vapor density (1-95% RH), 0.5 °C for dew point.
 Ranges. Multiple analog output ranges are available for all
measurement units (RH, DP, Pa, WVD).
 Flow Rate Range: 5 ml/min to 2000 ml/min.
 Intelligence. A built-in microcomputer monitors and controls all aspects of the RH-300's functions,
including mathematical calculations, diagnostics and communication.
 Ease of use. Measures dew point temperatures down to -40 °C without massive power requirements,
fans, or a reliable source of water for heat-sinking a mirror-chilling mechanism. A high-resolution analog
output (scaled according to function) and RS-232 serial data output are standard. Firmware upgrades,
user installable. Panel display is a clear 2 line, 16 character LCD. Size: 15 x 15 x 8 cm; Weight < 1 kg.
Power: external UL/CSA (supplied); requires 8-20 V at < 1W.
 Rugged. With no moving parts or fragile mirrors, the RH-300 is almost indestructible and is
warranted against failure for three years. The RH-300's internal sensor is not affected by most
particulate contaminants, or by condensation.
 WARRANTY: 3 years, Lifetime Technical Support.
Resolution: consider the ant: We chose an extreme
example to demonstrate our RH-300's resolution. We took
a single ant placed in an RC-M respirometry chamber, and
pulled dry, CO2-free air past it then through the RH-300 at
a controlled rate. The sudden, brief peaks are respiratory
water loss from the ant. These peaks occur when the ant
"breathes", or opens its respiratory system to the outside
air, losing water in the process. This is on top of a large
cuticular WL component (subtracted out in this example).
Other water vapor analyzers can’t begin to match this
resolution. Non-gravimetric determination of water loss rate is easily within reach, especially if
the RH-300 is used in its water vapor density mode – just multiply the reading by flow rate, and
you get water loss rate. A single instrument, the RH-300, can provide accurate water loss
readings from fruit flies through mice, rats, squirrels, and dogs to elephants, depending on your
flow configuration.
Consider your science. We designed the RH-300 for ease of
use, versatility and high resolution. With suitable calibration,
the accuracy of the RH-300 is equal to that of most high-quality
water vapor analyzers. Calibration is quick and easy, using
nitrogen or dried air and a fixed humidity source for a two-point
calibration - which is all you need, because of the RH-300's
almost perfect linearity. "Almost perfect linearity" is not mere selfpraise, as you can see from the graph at the left, the RH-300’s
linearity is better than 99.9% over the full scale of the instrument.
This gives you confidence in your measurements (see the skin
conductance graph to the right, conducted on a
human volunteer using a 5 cm2 flow-through skin
chamber). On the forehead trace you can see
individual sweat secretion events.
The standard for accuracy (as opposed to
resolution) in water vapor measurement is still the
chilled-mirror dew point analyzer. The RH-300
cannot claim better, or even equivalent, accuracy
compared to a high-quality analyzer of that type.
(Of course, it costs far less too). However, the
resolution and ease of use of the RH-300 are
unparalleled. If you need to measure relative
humidity, dew point, water vapor pressure or water vapor density with good accuracy and
superb resolution, the Sable Systems RH-300 will satisfy all of your requirements at a very
competitive price.
Throughout the broad spectrum of process
control, biological research, stored product
management, entomology, veterinary science,
respirometry and general industrial R&D, the
Sable Systems RH-300 has innumerable
applications. With this in mind, it's comforting to
know that the RH-300 not only boasts a threeyear warranty, but free, lifetime technical
support.
OPTION! The RH-300RS. For installations where it’s more convenient to use a compact remote sensor
(whether for reasons of space, environmental conditions or convenience), the RH-300 is available with a
remote flow-through sensor head instead of its interior sensor. The sensor head is approximately 2 x 3 x
1” (5 x 8 x 3 cm) and can be supplied with up to 20 meters (60 feet) of cable.
CONTACT US: For quotations or further information, call us at 800-330-0465/ 702-269-4445, FAX us at 702-2694446, or send email to mail@sablesys.com. For general information about Sable Systems or our other products,
you can also visit our World Wide Web site, http://www.sablesys.com.
Sable Systems was founded by scientists, for scientists.
You will enjoy doing business with us.