BS EN 60204-33-2011 pdf download.Safety of machinery Electrical equipment of machines Part 33: Requirements for semiconductor fabrication equipment.
Where two or more supply disconnecting devices are provided, interlocks shall be provided as necessary to prevent a hazardous situation.
When two or more supply disconnecting devices are present each shall be provided with marking such as WARNING: Risk of Electric Shock or Burn. Disconnect all (number of feed locations] sources of electrical supply prior to maintenance or repair
5.3.2 Type
The supply disconnecting device shall be one of the following types:
a) a switch-disconnector, with or without fuses, utilization category AC-23B or DC-23B:
b) a disconnector, with or without fuses, that has an auxiliary contact that in all cases causes switching devices to break the load circuit before the opening of the main contacts of the disconnector:
C) a circuit-breaker suitable for isolation:
d) a plug/socket combination under the following conditions:
• the plug/socket combination shall be connected so that the part connected to the incoming supply is protected to at least IP2X or IPXXB. and either
• the rated current does not exceed 16 A and total power rating does not exceed 3 kW: or
• where the rated current exceeds 16 A or the total power rating does not exceed 3 kW,
• it shall not be possible to connect or disconnect a plug/socket combination without adequate breaking capacity, during load conditions:
• where a plug/socket combination with breaking capacity is used, it shall have a breaking capacity of at least the rated current of the machine at rated voltage. Where a plug/socket combination is used for disconnection under overload (e.g. locked rotor), the rating should be at least locked rotor current. In addition, the electrical equipment shall have a device for switching the machine on and off.
NOTE For switch-disconnectors and disconnectors, see IEC 60947-3. For circuit.breakers sutabIe br isolation. see IEC 60947-2.
5.3.3 RequIrements
When the supply disconnecting device is one of the first three types specified in 5.3.2 (i.e. a
switch-disconnector, a disconnector used in combination with switching devices, or a
circuit-breaker), it shall fulfil all of the following requirements:
a) isolate the electrical equipment from the supply and have one OFF (isolated) and one ON position marked with “0” and “1” (symbols IEC 60417-5008 (2002.10) and IEC 60417- 5007 (2002.10), see 10.2.2); a ‘tripped’ position Is also permitted in the case of circuit- breakers:
The supply disconnecting device shall be installed in accordance with one or more of the following:
a) in its own electrical enclosure on or adjacent to the equipment for which it provides a disconnecting means;
b) near the top of the electrical enclosure for which It provides a disconnecting means;
C) anywhere below the top of the electrical enclosure for which it provides a disconnecting means provided that its incoming terminations are guarded to prevent accidental contact by personnel or by a tool dropped from above. Compliance can be demonstrated by verifying that a probe 3 mm in diameter and 15 mm long cannot contact live parts (see test probe 13 of IEC 61032).
EXCEPTION: Machines with a nominal power consumption of 1 500 W or less may be connected to a remotely mounted supply disconnecting device, provided that device Is readily accessible and no more than 6 m from the machine.
5.3.6 Supply disconnecting device door interlock
Doors that provide access to live parts of the supply disconnecting device, shall be interlocked so that the door can only be opened when the supply disconnecting device is open and so that the supply disconnecting device can only be closed when the door is closed.
A tool or special device as prescribed by the supplier may be provided to permit skilled and
instructed persons to defeat the interlock, provided that protection is provided against
inadvertent contact with hazardous-live-parts inside the enclosure by the measures defined In
6.5.
EXCEPTION: Supply disconnecting device door interlocking need not be provided where protection is provided against inadvertent contact with hazardous-live-parts inside the enclosure by the measures defined In 6.5 for loads that:
• are rated less than 5 KVA, or
• consist of lighting circuits, or
• are cord and plug connected electrical equipment.
5.3.7 UPS disconnection
The output of each UPS that can supply greater than 30 V r.m.s., 42.4 V peak, 60 V d.c. or 240 VA, shall be disconnected when the main disconnecting device is opened or shall be provided with a disconnecting means that satisfies all the requirements for the supply disconnecting device in 5.3.1 to 5.3.5, or both. The UPS output wiring and terminals shall be labelled as UPS Output”, or equivalent, at each connection point where the UPS wiring can be disconnected.BS EN 60204-33-2011 pdf download.