MANUAL
EFU10000
4.0kVA INVERTER UNIT
Pag. 27
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11.6. I
NPUT
P
ROTECTIONS
11.6.1 Inrush Current Limiter
A resistor shall limit Inrush Current
during start-up. When the Bus
Voltage stays over 330V
DC
for at least
3 seconds, the resistor is bypassed by
means of a relay.
11.7. B
RAKE
R
ESISTOR
C
OMMAND
P
ROTECTION
11.7.1 Brake Resistor
Overcurrent Protection
Limit
I
BR PROT
24 A
DC
±
5%
When current through brake resistor
overcomes I
BR PROT
, the brake resistor
is disconnected and RL2 is activated.
In any case heavy overloads, i.e.
brake resistor less than 10 , shall be
avoided.
11.8. DC BUS P
ROTECTINS
11.8.1 BUS Overvoltage
Protection – 1st Level
680V
DC
± 5%
When BUS Voltage reaches the
threshold of 680V
DC
±5% a Brake
Resistor is connected in parallel to the
BUS itself by means of an IGBT.
The protection will be automatically
disabled when BUS Voltage will
reach
a
value
of
600V
DC
±5%
(Hysteresis).
The resistor shall be on customer side,
while IGBT and its control are
integrated on the PCB.
11.8.2 BUS Overvoltage
Protection – 2nd Level
760V
DC
± 5%
When BUS Voltage reaches the
threshold of 760V
DC
±5%, inverter
output is switched off automatically
and RL2 becomes activated.
Engine must be switched off and the
full discharge of the BUS must be
waited before turning on the system
again.
