IEC/UL 60601-1 requirements and PEM solutions with filter by Schurter
Miroslav Piskor, a Product Specialist at SOS electronic, has prepared a summary of the basic requirements of the IEC/UL 60601-1 standard and solutions from Schurter. Thanks to these solutions, electrical devices containing their PEM with a filter meet the demanding requirements in healthcare and home care.
Protection of any power connection against unintentional removal of the plug from the equipment’s power socket.
- Cord retaining kits 4700.00XX
- Screw brackets for universal use 0888.00XX
- Power cord and PEM with V-Lock. Power socket is equipped with a notch that interlocks with a special latch on the connector on the power cord.
IP21 is required for all medical home care equipment (IEC 60601-1-11). Other medical applications may require even higher protection.
Power entry modules with protection against ingress of water:
- 5707: IP65 between PEM and device box and IP54 for connected power cord with V-Lock
- DG11, DG12: IP65 between PEM and device box and IP54 for connected power cord with V-Lock
Energized supply leads (L) have to be protected by a fuse to minimize the risk that if a failure occurs, the mains circuit breaker might be tripped and disconnecting other, maybe life-critical devices. In some countries the mains plug is not polarized => the power conductor could be on a neutral line! (e.g. CEE plugs in Europe)
PEM with a two-pole fuse holder is recommended for all medical electrical equipment.
Fuse holders can only be opened with the help of a tool (IEC 60601-1: 126.96.36.199, 8.11.5.).
PEM with the “Extra-Safe” fuse drawers and PEM with screw-in fuse drawers (5707 series).
Equipment should be completely disconnected from the power network after being turned off (IEC 60601-1: 8.11.1.).
PEM with a two-pole switch that disconnects the power feed on two poles.
Filter – Leakage Currents through PE (filter chassis)
Capacitors wired between the L, N, and PE are Y-capacitors. They produce a leakage current to PE. (current value depends on capacitance, the power-line voltage and frequency).
Leakage current for medical electrical equipment must not exceed:
- 100 µA for devices without direct operator contact, Means Of Operator Protection (MOOP)
- 10 µA for devices with direct patient contact, Means Of Patient Protection (MOPP)
(IEC 60601-1: 8.7.3.)
Power-line filters for medical electric equipment either have no (MOPP -> Schurter M5) or very small (MOOP -> Schurter M80) Y capacitors.
Filter – Safety Capacitors
Capacitors in power-line filters that are wired directly between the L and N conductors are X-class capacitors. Capacitors between L, N, and PE are Y-class capacitors.
Y capacitors in medical equipment:
- Class Y2 for equipment without direct patient contact (MOOP)
- Class Y1 for equipment with direct patient contact (MOPP)
(IEC 60601-1: 8.5.1.)
Schurter M5 PEMs with filter do not contain class Y capacitors. M80 PEMs with filter meet the requirements of IEC 60601-1: 8.5.1.
Filter – Energy Stored in Capacitors
If you unplug the power cord from the outlet, the voltage from the capacitors is present on the power pins until the capacitors are discharged.
1 second after unplugging the power cord, the voltage on the pins that can be touched by the operator must be a maximum of 60V (IEC 60601-1: 8.4.3.).
PEM with bleeder resistor between the phase and neutral conductors.
Filters – Attenuation
Filters with small Y capacitors (MOOP) or without Y capacitors (MOPP) have low high-frequency attenuation for asymmetric mode (L, N - PE). The situation can be improved a little bit by a filter with ground choke.
Attenuation of standard (1), M80 (2) and M5 (3) 1A filters and 1A M5 filter with ground choke (4).
Home Care Medical Equipment
IEC 60601-1-11 requires:
- Protection Class II (Double Insulation)
- Test voltage 4 000 V between L/N and the filter case
- Minimum protection against water IP21
- C8 or C18 inlet connectors (without PE)
- Reinforced insulation inside of the filter
- 8 mm surface and air distances between live parts and the filter housing
- PEM will withstand a test voltage greater than 4000 VDC between L/N and the filter housing
- Topology without Y capacitors
Are you interested in more information about Schurter products or technical advice when selecting a product? Or do you have another question or request? Feel free to contact us; we are happy to assist you.
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