FANOX SIA B, User Manual

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6.8.1.
Self-Powered relay with specific current transformers
The SIA-B powers itself from the operating current through specific current transformers that are
connected to the line. Self-power is achieved with very low levels of current: a minimum of
0.4xIsmin three phase current or 0.8xIsmin one phase. In other words, the SIA-B equipment starts
up from 3,2 A of three phase if the selected transformers are CT008 until 102,4 A for three phase if
the selected transformers are CT256.
The equipment is maintenance free when this type of power supply is used, as it does not require
auxiliary power components (batteries). As a result, it is especially useful in any centres where
auxiliary power is not available or cannot be guaranteed, and the facilities require protection with
low levels of current.
There is a self-power transformer per each phase (3 self-power transformers), separating current
circuits completely.
6.8.2.
230 Vac or 110 Vac, 50/60 Hz auxiliary power
The 230 Vac or 110 Vac auxiliary powers are taken from the transformation centre secondary
voltage. If this option is required, this needs to be selected in the list of models.
It is normal for transformation substations to have auxiliary voltage. This voltage is not guaranteed
because a short-circuit may cause this auxiliary voltage loss. However, the complete auxiliary
voltage loss is produced in primary faults between phases, which are very unlikely and generate a
lot of current. In other words, for faults with low contribution of current, AC auxiliary voltage keeps
its level and supplies the equipment and for faults with auxiliary voltage sag and high contribution
of current, the self-power characteristic keeps the equipment operative. The continuous operation
of SIA-B is guaranteed with the levels of self-power (0,4 x Ismin three phase current or 0.8xIsmin
one phase) and the auxiliary power supply 230Vac/110Vac.
6.8.3.
24 Vdc auxiliary power supply
The 24 Vdc auxiliary power is taken from the transformation centre RTU power supply. SIA-B
consumes a maximum of 0.5 W in normal operation. The consumption is so reduced that it
practically does not affect the transformation substation battery of 24Vdc, being able to supply
from it, with a total guarantee and without being a loss of functionality with communications
equipment because it will extract 20 mA/hour. Therefore, the equipment can be powered all the
time, allowing it to be continually monitored (status, measurements of transformation centre
current, events…). The equipment is totally operational at this power and if a fault occurs, the trip
time matches the time setting. In a situation where the centre is deenergized, if this is energized
and a fault induced with the instantaneous function set at 20 ms, the trip time will be 20 ms.
6.8.4.
Battery power: 5 V, with a KITCOM adaptor
The external 5 V battery is connected to the equipment through an adapter that is plugged into the
front communications port (KITCOM). It is useful for cases like commissioning operations,
discharges and repairs to the transformation centre, as these are situations when there is no
auxiliary voltage or current in the line and they normally cause more events, grounding, forgotten
tools, bad terminations, etc.
Battery power guarantees the full operation of the equipment, including the trip. The possibility of
using external battery power, together with the possibility of activating the trip contact from the test
menu, allows the trip circuit to be tested before the transformation centre is powered up.
Using battery power does not block the USB communications port, as it can be used
simultaneously.
When the equipment is being powered from a 5 V battery, it is capable of functioning for 4 hours.