General Description; Insulation Resistance Test Modes; Automatic Discharge; Lead Set - Megger BM5200 Manual Del Usuario

General description

BM5200 insulation tester has a digital and analogue arc display
designed for high voltage insulation resistance testing in the
maintenance and servicing of cables, rotating plant machinery,
transformers, switchgear and industrial installations.
DC insulation tests are performed at 250 V, 500 V, 1000 V, 2500
V and 5000 V. Insulation resistance measuring range is 100 kΩ to
1000 GΩ. Automatic discharge for capacitive circuits under test is
provided and decaying voltage displayed.
The guard terminal can be used to minimise the effects of surface
leakage and hence erroneous measurements when carrying out
insulation resistance tests.

Insulation resistance test modes

Three insulation resistance (IR) test modes are provided, (InS, PI, t)
and selected from any insulation range by pressing the left arrow
key depicting PI-t.
In insulation resistance test mode (InS) tests are initiated by pressing
and holding down the TEST button for two seconds. Once an
insulation test has initiated it will terminate on the next press of
the TEST button. The reading is held on screen until TEST is
pressed again or another range is selected.
A Polarisation Index (PI) mode performs a ratiometric test that
calculates the ratio of insulation resistance at ten minutes to
insulation resistance at one minute.
The timer (t) mode facilitates a single fixed duration IR test based
on the set time interval t.
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Automatic discharge

For capacitive test objects the instrument will automatically dis-
charge through an internal resistor and indicate voltage across
the terminals in the range 25 V to 600 V with higher voltages
indicated by '>600 V'. This feature will give decaying voltage
indication
following the testing of equipment possessing capacitance. When
the voltage indicator no longer shows it is safe for the user to
disconnect the test leads.

Lead set

Three recessed sockets are provided, and marked '+', '-' and 'G'.
These have safety covers which open when the plugs are inserted.
When inserted into the sockets, the shrouded test lead plugs lock
into position. They are released by twisting the plug a quarter turn
and pulling out.
For this reason, only the test leads supplied or suitable Megger
replacement ones should be used.

Instrument power

The BM5200 is powered by eight 1.5 V IEC LR6/AA alkaline cells.
Rechargeable batteries should not be used on this instrument.

Instrument safety

Design safety features include:
External voltage indication, AC or DC displayed.
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Load automatically discharged at the end of a test, and
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decaying voltage displayed.
Test leads can lock into the case to prevent accidental disconnection.
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