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Series 7400 Single Phase 1+N UPS
1.3 Safety Precautions
In common with other types of high power equipment, dangerous
voltages are present within the UPS and battery enclosure. The risk
of contact with these voltages is minimised as the live component
parts are housed behind a hinged, lockable door. Further internal
safety screens make the equipment protected to IP20 standards.
No risk exists to any personnel when operating the equipment in
the normal manner, following the recommended operating
procedures.
All equipment maintenance and servicing procedures involve
internal access and should be carried only by trained personnel.
Battery manufacturers supply details of the necessary precautions
to be observed when working on, or in the vicinity of, a large bank
of battery cells. These precautions should be followed implicitly at
all times.
Particular attention should be paid to the recommendations
concerning local environmental conditions and the provision of
protective clothing, first aid and fire-fighting facilities.
When the battery is charge it is earth-referenced about it is mid-
point -e.g. if the battery is being charged at 432V the battery
extremities will be at +216V and - 216V with respect to neutral
(earth). When using mains-powered test equipment such as
oscilloscopes in the UPS high voltage area, always use a differential
mode of operation to avoid the need to disconnect the oscilloscope
frame earth.
When working inside the UPS (trained personnel only) it is
recommended that protection be worn to prevent eye damage,
should an electrical arc be struck by mishandling or severe
electrical fault.
Some of the power components are very heavy. If their removal is
necessary ensure that sufficient manpower is available, otherwise
use adequate mechanical handling equipment.
When working in the general area of the UPS where high voltages
are present, a second person should be standing-by to assist and
summon help in case of accident.
1.3.1 General
1.3.2 Batteries
1.3.3 Test Equipment
1.3.4 Personnel