PROTECTION DEVICES AND SAFETY
E
LECTROMAGNETIC COMPATIBILITY
This uninterruptible power supply (UPS) is a product which respects the provisions of class C3 of the standards currently
in force as regards electromagnetic compatibility.
CAUTION:
This product is designed for commercial and industrial application in the second environment – during installation, it may
be necessary to add certain restrictions and adopt additional measures in order to prevent disturbances.
P
ROTECTION AGAINST OVERVOLTAGE
The UPS has been designed to be powered by an AC source with category 2 spike voltage. If the UPS is connected to
AC sources with different characteristics or if the UPS is at risk of overvoltage, even temporarily, suitable external
protection devices must be installed.
P
ROTECTION AGAINST SHORT CIRCUITS
In the presence of a fault on the load, in order to protect itself, the UPS limits the value and the duration of the current
supplied (short circuit current). These quantities are also functions of the operating status of the unit at the moment of the
fault; two different cases can be distinguished:
UPS in NORMAL OPERATION MODE: the load is instantly switched to the bypass line (I
input line is connected to the output without any internal protection (locked after t>0.5s)
UPS in BATTERY OPERATION MODE: the UPS protects itself by supplying output current which is 1.5 times
the rated current for 0.5s, switching off after this time.
P
ROTECTION AGAINST BACKFEEDING
The UPS is equipped with an internal protection device against backfeeding using metal separation devices.
The UPS has an internal device (redundant bypass power supply) which, in the event of a fault with the
machine, activates the bypass automatically, ensuring load feeding continues without any internal protection
nor limit of the power supplied to the load. In this emergency condition, any disturbance present on the input
line also affects the load. See also the "Redundant auxiliary power supply for automatic bypass", paragraph in
the "USE" section.
E
XTERNAL PROTECTION DEVICES
FUSES / CIRCUIT BREAKERS
On the UPS input line, in a dedicated panel, a device to protect against overcurrents must be envisaged
This protection device can be created with gG fuses, as shown in the table, or with an equivalent circuit breaker. With a
separate power input, main line + bypass line, two protection devices are required, one for each line present.
UPS model
100
120
* inside the UPS, on the bypass line, no maximum current protection is envisaged. This protection must be envisaged in the
system based on the I2t indications described in the "Protection against short circuits" paragraph
If the protection device upstream from the UPS interrupts the neutral conductor, it must also interrupt all the
phase conductors as the same time (four pole switch).
IV333 Rev.000 SIEL S.p.A.
Data di emissione: 2011-09-28
External AC protection devices
Mains input
250A
250A
2
t=125000A
Separate bypass input *
250A
250A
Pag. 68 di 246 + FR
2
s): the