TESTO 6681 Instruction Manual page 61

A 2-point adjustment cancels any previous 1-point
adjustment.
Adjustment with the standard Testo adjustment salt pots is
not suitable for the testo 6614 (heated for high-humidity
applications) and testo 6615 (trace humidity) probes. The
reference conditions should be generated in a humidity
generator to adjust these probes.
In addition, these probes can also be adjusted at a third
adjustment point by Testo Service.
testo 6614: third adjustment point at 90 % RH

testo 6615: third adjustment point at -40 °Ctd/-40 °Ftd.

testo 6681 Ethernet
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