Features - Megger BM11D Manual Del Usuario

Sliding cover
The sliding cover ensures that the input and the output
terminals cannot be accessed simultaneously.
Terminals
The terminals marked '+', '–' and 'G' lock the test leads into the
case to prevent accidental disconnection.
Terminal Voltage
At the end of a test, any voltage remaining on the terminals will
be indicated until it has decayed to less than 50 V.
BM21:Output terminal voltage is indicated during a test.
Timer
BM11D:The timer automatically starts when the test button is
pressed. It indicates the time elapsed. Maximum test duration is
60 minutes, when the test will be stopped automatically.
BM21: The test time can be set by the user. Selecting
using the selector keys, and using the range keys to ramp the
time up or down will set the duration of test. (Maximum 90
minutes). The timer will automatically start when the test button
is pressed, and will stop when the test duration has elapsed
(unless stopped in one of the other ways). Setting the timer to
zero minutes effectively disables the instrument. A test time of
10 minutes is useful for Polarisation Index (PI) testing.
For more information on PI testing, see 'Application of Test
techniques'.

FEATURES

Automatic Discharge
Internal discharge resistors will be selected automatically
1) At the end of a test
2) If the instrument is switched off
3) If an internal error is detected
Variable Voltage (BM21 only)
The variable voltage position provides the user with the option
to select a non-standard voltage between 25 and 5000 V d.c.,or
to continuously vary the voltage selected (in 25 V steps) during
a test.
When operating on this range, the measurement range (either
'R', 'I' or 'BURN') cannot be changed. The measurement range
must therefore be selected before the variable voltage position
is chosen.
To select the test voltage required, move the cursor to the
position and adjust the output terminal voltage using the Range
keys. The terminal voltage is shown at the top of the display.
BURN Mode (BM21 only)
Selecting 'BURN' mode will enable testing to continue after a
breakdown, for fault location. Under some conditions, the
breakdown will cause erratic display operation.The burn mode
can only be selected before a test is started.
The detachable lid
Specially designed lid hinges enable the lid to be removed and
replaced as required, and will protect the lid from strain or damage
by unclipping itself if unintentionally opened past its full extent.
To replace the lid, hold it vertically and push the hinges back
into their clips again while restraining the instrument. Then fold
the lid shut.
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