Operation Manual

GMC-I Messtechnik GmbH 15
5 Classification of Devices Under Test
5.1 Safety Classes
Devices assigned to all of the following safety classes are equipped with
basic insulation, and provide for protection against electrical shock by
means of various additional precautions as well.
Safety Class I Devices
Exposed, conductive parts are connected to the protective conductor so
that they are not charged with voltage if the basic insulation should fail.
Safety Class II Devices
These devices are equipped with double insulation or reinforced insula-
tion.
Safety Class III Devices
and Devices with Internal Power Supply
These devices are powered with Safety Extra Low Voltage (SELV). Beyond
this, no voltages are generated which exceed SELV. These devices may
not be connected to the mains. They may only be connected to the test
instrument at jacks 1 through 3.
Note: The DUT may only be connected to jacks 1 to 3 at the test instru-
ment. It is only possible to perform a visual inspection, a measurement of
the insulation resistance or the supply voltage, see parameter “SC III U
V
”
on page 39.
Classification Parameter (in the Sequence ... menu)
The test instrument always performs testing in accordance with the strict-
est limit values of the respectively selected safety class. The test is failed if
this limit value is exceeded.
However, higher limit values are allowed for certain devices under test.
If the classification parameter has been activated (= x), the user is asked if
higher limit values are allowable for these devices. If the user responds
with “Yes”, the DUT is reevaluated and the test may be passed.
Devices with Internal Power Supply
Devices with internal power supply are tested like permanently connected
Safety Class II or III devices.
5.2 Application Parts (electrical medical devices)
Type B Application Parts (body)
Devices of this type are suitable for both internal and external patient
applications, except for use in direct proximity to the heart.
These devices provide for adequate protection against shock especially
as regards:
• Reliable leakage current
• Reliable protective conductor connection if utilized
Devices of the following safety classes are allowable:
I, II, III or devices with internal electrical power supply.
Type BF Application Parts (body float)
Same as type B, but with type F insulated application parts.
Type CF Application Parts (cardiac float)
Devices of this type are suitable for use directly at the heart. The applica-
tion part may not be grounded.
Devices of the following safety classes are allowable:
I, II or devices with internal electrical power supply.