Xantrex Technology SW5548 - Manual (Page 6)

©2000 Xantrex Technology Inc.
Over/Under Voltage Fluctuations
*“Trip time” refers to the time between the abnormal conditions being applied and the inverter
ceasing to energize the utility line.
Over/Under Frequency Disturbances
Small renewable energy systems are allowed to sell within a fixed frequency range of -0.7 Hz/
+0.5 Hz of the nominal frequency in which they will operate. When the utility frequency is outside the
range of the nominal frequency window, the inverter must cease to energize the utility line within 6
cycles.
Reconnect Delay After a Utility Disturbance
An unacceptable utility event causes the renewable energy system to disconnect from the utility
line. It will remain disabled until acceptable voltage and frequency have been maintained for a
minimum of five minutes. After the 5 minute timer is complete, the inverter is allowed to
automatically reconnect the renewable energy system to the utility.
Islanding Protection
The non-islanding inverter protection features required by UL1741 ensures that the inverter
ceases to energize the utility line when the inverter is subjected to island conditions. As a result,
active control techniques have been incorporated into the SW inverter for detecting potential
dispersed-generation islands.
A utility wishing to ensure against renewable-energy supported dispersed-generation islanding
may require the use of a non-islanding inverter. Trace™ has designed the new software protection
system to comply with the requirements of the non-islanding inverter section of UL1741.
Over-current Protection
The Trace™ SW Series inverters also include over-current protection for the inverter system.
This protective system is used if the inverter attempts to power too large of a load or if the inverter
loses synchronization with the utility grid. This protective system is implemented with redundant
systems in analog hardware, microprocessor software and with a mechanical device (circuit
breaker). This insures the inverter is protected from damage and can not create an unsafe fault
condition to the utility or residence.
VOLTAGE MAXIMUM TRIP TIME*
Voltage < 60 V (< 50%) 6 cycles
Voltages between 60–106 V (50–88%) 120 cycles
Voltages between 106–132 V (88–110%) Normal operation
Voltages between 132–165 V (110–137%) 120 cycles
Voltage >165 V (137%) 2 cycles
FREQUENCY MAXIMUM TRIP TIME*
Frequency < 59.3 Hz 6 cycles
Frequency > 60.5 Hz 6 cycles
976-0013-D-002
ADDENDUM
4