Hach TU5200, User Manual, Page: 36 / 40

Message Solution
Measured with different
calibration. Read standard? The verification standard was measured for a different calibration curve (e.g.,
StablCal, Formazin, SDVB, degrees or custom).
Measured with different
instrument type. Read
standard? The verification standard was measured on a different type of instrument (e.g.,
different lasers).
Remove air bubbles from the sample
Air bubbles can cause unstable readings. Use a degassing method to remove air or other gases from
the sample before measurement even if no bubbles are seen.
The methods typically used for degassing are:
• Let the sample stand for several minutes
• Apply a vacuum
• Use the sample degassing kit
• Use an ultrasonic bath
Let the samples stand for several minutes, then gently invert two or three times before measurement.
In some cases, more than one method may be necessary to remove bubbles (e.g., the use of heat
with an ultrasonic bath may be necessary in some severe conditions). Use care with these methods
as sample turbidity can be changed if these methods are not used correctly.
Condensation
If condensation collects on the sample vial during measurement, let the sample become slightly
warmer before measurement. Keep the sample at room temperature or partially put the sample vial
into a warm water bath for a short time.
Note: A temperature increase can change the sample turbidity. Measure the sample before the temperature
increases when possible.
Replacement parts and accessories
W A R N I N G
Personal injury hazard. Use of non-approved parts may cause personal injury, damage to the
instrument or equipment malfunction. The replacement parts in this section are approved by the
manufacturer.
Note: Product and Article numbers may vary for some selling regions. Contact the appropriate distributor or refer to
the company website for contact information.
Recommended standards
Description Quantity Item no.
Verification standard, < 0.1 NTU, glass verification rod (solid
secondary standard)
each LZY901
StablCal kit, sealed vials with RFID, includes:
10, 20 and 600 NTU vials
each LZY835
StablCal 20-NTU sealed vial with RFID each LZY837
StablCal 600-NTU sealed vial with RFID each LZY838
StablCal kit, sealed vials without RFID, includes:
10, 20 and 600 NTU vials
each LZY898
StablCal 20-NTU sealed vial without RFID each LZY899
StablCal 600-NTU sealed vial without RFID each LZY900
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