5.8. Dielectric Absorption Index (DAI)
The
key makes it possible to visualize the Dielectric Absorption Index
value on the display. For this kind of test, the equipment should be
connected, applying voltage to the sample for 60 seconds. After this
period, the operator must press the
value on the display. If this key is pressed before the 1-minute period has
elapsed, the display will show DAI = - - -.
The Dielectric Absorption Index is the ratio between the insulation
resistance value measured after 60 seconds and the value measured
after 30 seconds. This value is useful to determine whether it is necessary
to perform preventive and predictive maintenance on the coils
(transformers, engines and motors, generators, etc.).
5.9. Internal memory
This equipment has an internal memory for up to 4000 measured values.
This memory is administrated by the instrument and works in a cyclic
way, this means, when the memory is full, the oldest values in the
memory will be replaced by the newest ones. To avoid lost of data,
always download the internal memory after finish the measurements.
5.10. Auto power-off
The Auto-Power-off function turns off the equipment consumption
(independently of the timer function) in two situations:
During the measurement - After 35 minutes of operation, without
•
allowing that the battery status checking function is carried out during
that period.
Idle equipment - After 10 minutes of inactivity.
•
key to read the absorption index
R
=
60 seconds
DAI
R
30 seconds
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