Stahl 8571/51-4, Operating Instructions Manual

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Special conditions for safe use
14
Maintenance socket isolator 8571/51
eng
li
sh
3 Special conditions for safe use
Use a padlock to safeguard the maintenance socket isolator against unauthorised use.
Commissioning a maintenance socket isolator requires the approval of the plant opera-
tor or his authorised agents. Such approval may only be given after it is ascertained
that a potentially explosive atmosphere does not exist during the period in which repair
work is performed, or that necessary protective measures have been taken to avoid the
danger of explosion. The maintenance socket isolator may only be put into operation
with a work release in accordance with Directive RL 99/92/EG, Annex II 1.2.
4 Conformity to standards
The devices comply with the following standards and directives:
• Directive
2014/34/EU
• EN 50 014, EN 50 018, EN 50 019, EN 50 020, EN 60 241-0, EN 60 241-1
• IEC 60 079-1, IEC 60 079-7, IEC 60 079-11, IEC 61 241-1
• IEC 60 947-3, IEC 60 947-4-1, IEC 60 309, IEC 60 529
The devices are approved for use in hazardous area Zones 1, 2, 21 and 22.
5 Function
5.1 Function of the maintenance socket isolator
The maintenance socket isolators are explosion-protected electrical apparatus. They
are used for commissioning portable and permanently installed non-explosion-protected
electrical apparatus, or plugs and socket receptacles located within hazardous areas
during periods when a potentially explosive atmosphere is not present (e.g. during repair
and maintenance work requiring high-temperature approval).
The maintenance socket isolator is constructed as per the following concept:
The entire enclosure and the connection technology contained within correspond to the
requirements of type of protection Increased Safety „e".
The switching contact compartment of the panel-mountable switch is suitable for the
safe isolation of supply voltage from non-Ex socket receptacles and signal lamps/fuses.
Moreover, the rated voltage is so reduced that the clearance and creepage distances
within the flameproof enclosed switch chamber also meet the requirements of Increased
Safety "e".
5.2 Function of indicating lamp Type 8010/...
The indicating lamp displays the current state of a command by either switching on or
switching off a light signal. In combination with a switchgear device, they indicate the
switching state.
The light signal is displayed from the enclosure via the transparent lamp insert cover
equipped with a diffuser lens.
The design of the indicating lamp is based on light-emitting diode (LED) technology.
Class 1 light-emitting diodes are employed in accordance with DIN EN 60 825-1.