In-Situ TROLL 9500 Operators Manual - Manual (Page 156)

151 0095110 rev. 007 01/09 TROLL 9500 Operator’s Manual
Reading: Measurement from a single channel (parameter).
Redox potential, see Oxidation-reduction potential
Reference (water level measurements), see Level reference
Reference electrode: A standard electrode of known potential against
which the measurement or sensing electrode is compared.
Repeatability: Closeness of the agreement between the results of suc-
cessive measurements carried out under the same conditions.
Reproducibility: Closeness of the agreement between the results of
measurements of the same measurand carried out under nearly
identical conditions but after an intermediate change was made
and removed.
Resistance thermometer: Temperature sensor that changes electrical
resistance with temperature.
Resistivity: The reciprocal of conductivity; calculated from conductivity.
Resolution: The smallest unit that can be measured by a device over
its full range.
Response time: Time required for the MP TROLL to power a sensor
and the sensor to return an accurate reading.
Restrictor: Perforated stainless steel area of the MP TROLL 9500
between the nose cone and the body; protects the sensors and
allows free circulation of environmental fluid.
RDO: Rugged optical dissolved oxygen sensor
RS-485: Communications protocol using Recommended Standard
485 of the Electronic Industries Association (EIA-485) for the
orderly transfer of electrical data signals; a balanced (differential),
multipoint Interface Standard that uses two lines to transmit/receive
data and can operate at 100 Kbps with cable lengths up to 4000
feet.
RTD: Resistance temperature detector, a type of resistance thermom-
eter that has nominally 100 7
RuggedCable™: Waterproof, submersible, TPU-jacketed vented
or non-vented cable for a Multi-Parameter TROLL 9500; carries
power and communication signals; provides strain relief and a
means to anchor the instrument to a stationary object; Twist-Lock
connectors on both ends, Rugged (titanium) or Standard (carbon-
filled ABS plastic); halogen-free version available.
S, see Siemens
Salinity: A measure of the amount of salts dissovled in water, usually
expressed in parts per thousand (ppt); calculated from conductivity
and temperature.
Saturation: The point at which a substance contains a maximum
amount of another substance at a given temperature and pressure.
3#
SDI-12: A serial-digital interface operating at 1200 baud.
Sensor kit: Package containing an In-Situ sensor, along with neces-
sary installation items and instructions for installing in the Multi-Pa-
rameter TROLL 9500.
SI: International System of Units.
Siemens (S): SI unit for conductivity, reciprocal of the ohm; this unit
was formerly known as the “mho” (ohm spelled backwards).
Site node: Topmost node in the Win-Situ or Pocket-Situ Navigation
tree, representing the host computer.
Slope: Sensor response vs. concentration (quantity). Slope and offset
are the coefficients calculated during calibration that convert ana-
log measurements to user units.
Slug test: Aquifer characterization test that involves “slugging” a well
with a known volume of fluid or solid and measuring the time of
recovery to stable conditions.
Soak time: Length of time a sensor is immersed in a calibration solu-
tion or sample, ideally at the same temperature at which measure-
ments will be taken.
Sodium nitrate (NaNO
3
): A salt used to make nitrate calibration stan-
dards.
3PECIFIC
Standard Methods: Approved methods of analyzing for water-quality
parameters, as specified in the reference work Standard Methods
for the Examination of Water and Wastewater, published jointly by
the American Public Health Association, American Water Works
Association, and Water Environment Federation.
Stirrer: Battery-powered motorized low-power stirring mechanism with
magnetic stirring bar for use during calibration and/or in stagnant
waters.
Submersible cable: Waterproof, quick-connect cable designed for sub-
mersion; Instrument backshell located at downhole end; surface
connector at surface end.
GLOSSARY