Benning ST 755+ - Protective Conductor Current; Contact Current; Device Leakage Current (Medical Electrical Devices)

7.7 Individual tests
Functions
5284 / 08/2023 enBENNING ST 755+ / ST 760+44
7.7.3 Protective conductor current
EN50678 (VDE0701)
EN50699 (VDE0702)
EN62353
(VDE0751‑1)
EN60974‑4
(VDE0544‑4)
ClassI ClassII ClassIII ClassI ClassII ClassI ClassII
X - - X - X -
For test samples of protection classI, the protective conductor current is tested at mains voltage
to check it for proper insulation capacity. This is to ensure that no leakage or fault current flows
from the active components to earth and that there is no risk of a dangerous electric flow via
accessible conductive components [}page83].
7.7.4 Contact current
EN50678 (VDE0701)
EN50699 (VDE0702)
EN62353
(VDE0751‑1)
EN60974‑4
(VDE0544‑4)
ClassI ClassII ClassIII ClassI ClassII ClassI ClassII
X X X
(optional)
X X X X
The contact current must be measured on every accessible conductive component without
protective conductor connection [}page84].
This is to ensure that there is no risk of a dangerous electric flow via accessible conductive
components. Accessible conductive SELV/ PELVjacks can optionally be scanned, provided
that no damage to the test sample has to be expected.
For this purpose, the following measuring methods may be used:
• Direct current measuring method (direct measuring method)
• Differential current measuring method
• Alternative leakage current measuring method
7.7.5 Device leakage current (medical electrical devices)
EN50678 (VDE0701)
EN50699 (VDE0702)
EN62353
(VDE0751‑1)
EN60974‑4
(VDE0544‑4)
ClassI ClassII ClassIII ClassI ClassII ClassI ClassII
- - - X X - -
The device leakage current corresponds to the sum of all leakage currents and is tested at
mains voltage for medical devices of protection classesI andII to prove proper insulation
capacity. This is to ensure that no leakage current flows from the active components, the
housing or accessible conductive components to earth and that there is no risk of a dangerous
electric flow via accessible conductive components [}page86].
For this purpose, the following measuring methods may be used:
• Direct current measuring method (direct measuring method)
• Differential current measuring method
• Alternative leakage current measuring method