Sample requirements, Sample measurement, Measurement notes – Hach-Lange SENSION+ 50 49 User Manual User Manual
Page 11
Sample requirements
The multisensor probes are not compatible with specific sample types. Probe damage can occur if
used in non-compatible samples.
• Samples should be aqueous. Measurements may be made in partially aqueous or some water-
miscible solvents. The results must be interpreted with caution as the full pH scale is shifted when
the solvent system changes.
• The multisensor pH probe is not compatible with solutions that contain silver complexing or binding
agents such as TRIS, proteins and sulfides.
• Proteins can collect on the probe sensors. Make sure the probes stay clean when these types of
samples are measured.
• Do not use multisensor in solutions that are outside the specified temperature range. Refer to
on page 3.
Sample measurement
W A R N I N G
Chemical exposure hazard. Obey laboratory safety procedures and wear all of the personal protective
equipment appropriate to the chemicals that are handled. Refer to the current safety data sheets
(MSDS/SDS) for safety protocols.
N O T I C E
Do not immerse the multisensor if a probe is not connected. Damage to the mini-MP connector will occur.
Before measurement:
Prepare the probe(s) for use. Refer to
on page 5.
Calibrate the probe(s). Refer to
on page 5. The manufacturer recommends to calibrate at least once
a day for the best measurement accuracy.
Measurement notes
• The calibration and sample measurement conditions must be as similar as possible (e.g., the
temperature of the solution, stir procedure, stir rate and position of the probe).
• Do not dilute conductivity standards or samples.
• When the probe is submerged, make sure that there are no air bubbles under the probe tip. Gently
shake the probe from side to side to remove any air bubbles.
• Make sure that the reference junction on the pH probe is fully immersed in the solution.
• If necessary, turn the protective shroud and remove it from the probe. The manufacturer
recommends to measure with the protective shroud installed. The protective shroud prevents
damage to the sensors.
• Do not put the probe on the bottom or sides of the container.
• If the stabilization is slow, shake the multisensor from side to side in the solution.
• Do not use probes in areas where EMF is present (i.e., voltaic cells, thermoelectric devices,
electrical generators, resistors and transformers). For use in process units (i.e., spot checking),
make sure that the meter is grounded.
• If a measurement error occurs, refer to
English 9