Borri ASD91, Operating Manual

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Installation and start-up of UPS B8000FXS 10-60kVA
Installazione e avviamento UPS B8000FXS 10-60kVA
OMD91050 REV. G 27
The electrical connection is part of the work which is normally provided by the company that
carries out the electrical installation and not by the UPS manufacturer. For this reason, the
following recommendations are only an indication, as the UPS manufacturer is not responsible
for the electrical installation. In any case we recommend to carry out the installation and the
electrical input and output connections in compliance with the local standards.
Cables must be selected bearing in mind technical, financial and safety aspects. The
selection and the sizing of cables from a technical viewpoint depend on the voltage, on the
current absorbed by the UPS, on the bypass line and on the batteries, on the ambient
temperature and on the voltage drop. Finally, the kind of cable laying must be taken into
particular consideration.
For more explanations regarding the selection and the sizing of cables, please refer to the
relevant IEC standards, in particular to IEC 64-8 standard.
“Short-circuit currents” (very high currents with a short duration) and “overload currents”
(relatively high currents with a long duration) are among the main causes of cable damage. The
protection systems normally used to protect the cables are: thermal magnetic circuit breakers or
fuses. Protection circuit breakers must be selected according to the maximum short-circuit
current (max Isc) that is needed to determine the breaking power of automatic circuit breakers,
and to the minimum current (min Isc) that is needed to determine the maximum length of the
line protected. The protection against short-circuit must operate on the line before any thermal
and electrothermal effects of the overcurrents may damage the cable and relevant connections.
During the electrical installation take particular care to respect the phase rotation.
- UPS up to 20kVA
The terminal boards are placed on the rear of the UPS, under the breakers. To access the
terminals remove the protection, removing the fixing bolts.
- UPS 30...60kVA
The terminal boards are placed on the front of the UPS. To access the terminals remove the
front panel, removing the fixing bolts.
Mains connection
The connection to the mains must be carried out with protection fuses between the
mains and the UPS.
The use of differential protection devices in the line supplying the UPS is
unadvisable. The leakage current to ground due to the RFI filters is rather high
and it can cause spurious tripping of the protection device.
According to CEI EN62040-1 standard, in order to take into account the UPS’
leakage current, residual current devices having adjustable threshold can be used.
Mains connection
Include an appropriate and readly accessible disconnect device in the fixing
wire connecting the UPS to the mains.