Check Of The Circuit Separation - Amprobe MultiTest 1000 Manual Del Usuario

11.4.

CHECK OF THE CIRCUIT SEPARATION

PURPOSE OF THE TEST
The test, to be performed in case the protection is realized through separation (64-8/6
612.4, SELV or PELV or electrical separation), shall check that the insulation resistance
measured according to the indications below (depending on the separation type) complies
with the limits reported in the table relative to the insulation measurements.
INSTALLATION PARTS TO BE CHECKED
•
SELV system (Safety Extra Low Voltage):
Measure the resistance between the active parts of the circuit under test (separate)
and the active parts of the other circuits.
Measure the resistance between the active parts of the circuit under test (separate)
and the earth.
The resistance shall not be lower than 0.25MΩ with a test voltage of 250VDC.
•
PELV system (Protective Extra Low Voltage):
Measure the resistance between the active parts of the circuit under test (separate)
and the active parts of the other circuits.
The resistance shall not be lower than 0.25MΩ with a test voltage of 250VDC.
•
Electrical separation:
Measure the resistance between the active parts of the circuit under test (separate)
and the active parts of the other circuits.
Measure the resistance between the active parts of the circuit under test (separate)
and the earth.
The resistance shall not be lower than 0.5MΩ with a test voltage of 500VDC and 1MΩ with
a test voltage of 1000VDC.
ALLOWABLE VALUES
The test result is positive when the insulation resistance indicates values greater or equal
to those indicated in the table reported in the section relative to insulation tests.
Please note that:
A SELV system is a system of category zero or very low safety voltage featured by:
independent source (ex. batteries, small generator) or safety (ex. safety transformer)
power supply, protection separation to other electrical systems (double or reinforced
insulation or a metal screen connected to the earth) and no earthed points (insulated from
the earth).
A PELV system is a system of category zero or very low safety voltage featured by:
independent source (ex. batteries, small generator) or safety (ex. safety transformer)
power supply, protection separation to other electrical systems (double or reinforced
insulation or a metal screen connected to the earth) and there are earthed points (not
insulated from the earth).