Hach-Lange SENSION+ 50 49 User Manual - Manual (Page 7)

Meter compatibility
The 50 49 multisensor is compatible with the sensION+ handheld meter models: MM156 and
MM156 DL.
Preparation for use
C A U T I O N
Personal injury hazard. Broken glass can cause cuts. Use tools and personal protective equipment to
remove broken glass.
To prepare the probes for calibration or sample measurement:
1. Turn the protective shroud and remove from the multisensor.
2. Turn the probe storage tube(s) and remove from the probe(s). Keep the probe storage tube(s).
3. For conductivity probes: Before initial use, soak the probe sensor in ethanol for 15 seconds.
4. For dissolved oxygen probes: refer to
Polarize the dissolved oxygen probe on page 5.
5. Rinse the probe(s) with deionized water. Blot dry with a lint-free cloth.
Polarize the dissolved oxygen probe
Before calibration or measurement of dissolved oxygen with the multisensor, polarize the dissolved
oxygen probe.
The dissolved oxygen probe must be polarized every time the multisensor is disconnected from the
meter or the batteries are removed from the meter. The probe is continuously polarized while it is
connected to the meter.
1. Fill the DO membrane module. Refer to Fill the membrane module on page 12
2. Install the membrane module.
3. Connect the multisensor to the meter. Set the meter to on.
4. Let the dissolved oxygen probe to polarize. Refer to
Table 1 for the amount of time.
5. Enter the atmospheric pressure and salinity on the meter. Refer to the meter manual.
Table 1 Polarization times
Disconnect time Polarization time
Less than 5 minutes 10 minutes
5–15 minutes 45 minutes
More than 15 minutes 6 hours
Calibration
Before calibration:
Prepare the probe(s) for use. Refer to Preparation for use on page 5.
Prepare the meter. Refer to the meter manual.
Calibration notes
• For maximum accuracy, calibrate the probe at least once a day.
• Prepare fresh standard solutions for the calibration.
English 5