HYDAC HLB 1300 - Manual (Page 21)

User Manual HYDACLab ® 23.10.2008
6
Explanation of status signal:
Status Status signal (mA)
Optimization phase 5
Operating phase 7
Optimization phase
(temperature and/or
humidity have reached
the warning limit) 9
Operating phase (1 or
several measurement(s)
have reached the
warning limit) 11
Device error ≥ 13
Note: Due to possible tolerances, we recommend setting the threshold in the evaluation electronics
approx. 0.25 mA below the ideal value given in the table.
5. Startup
HYDACLab ® sensors start storing data as soon as they have been connected to the supply
voltage and fluid temperature has exceeded 25°C for the first time. The output signals for
temperature and relative humidity are available immediately following sensor startup. The output
signal for relative change in dielectric constant is displayed after approx. 5 minutes.
During an optimization phase (duration of data collection: approx. 100 hours in the valid operating
range) the HYDACLab
®
sensor monitors the particular fluid properties and adapts itself to the
conditions in the given application. It is therefore essential that typical operating conditions,
particularly all relevant temperature ranges, are run through during the optimization phase.
Termination of the optimization phase will be evident from the signal level of the status signal (see
Chap. 4.2).
During the optimization phase, the user must ensure therefore that the HYDACLab
®
is only
supplied with voltage if the operating conditions in the machine/system are normal.
(For example, the supply voltage of the sensor can be linked to the pump operation.)
The sensor should be reset if, after the machine/system is part-filled or re-filled, the analogue
values for the relative change in dielectric constant do not fall within a window of
± 5 %. This can
be caused by sometimes obvious variations in oil characteristics in different oil batches.