Today's Industrial Products and Solutions February 2019 | Page 9

The first is to install dedicated lighting fixtures that can be sized to meet full building load require-
that provide temporary power from built-in bat- ments for power up to 18,000 watts. 
tery packs.  The other is to utilize centrally located
inverters tied to back-up batteries that can provide
utility-grade power to both existing architectural
and dedicated emergency lighting in the event of a
power outage.
For engineers that must select an inverter, calculat-
ing the size needed as well as AC load requirements
is a relatively simple matter. 
In order to meet safety and regulatory requirements
for emergency lighting, one of the most important
capabilities of advanced inverters is the ability to
automate testing and reporting functions.
NFPA code requires that emergency lighting systems
are tested for 10 minutes every 30 days, and to be
discharged for 90 minutes once annually.  Records
must be kept for review by Fire Marshalls or other
However, there are multiple factors that should also officials that make periodic inspections of emergen-
be considered in making a final inverter selection cy lighting systems.
that best suits the application.  These include select-
ing inverters that provide pure sine wave AC power,
operate at their designated rating, and provide auto-
mated testing/reporting.
Given the increasing use of LEDs in architectural
lighting, it is important to select an inverter that
incorporates pure sine wave technology. 
The more advanced inverter systems keep a record
of all of that information.  A Fire Marshall can simply
review the logs and see the testing was automatical-
ly performed as scheduled as well as see any alarms.
The inverters can also be controlled through a
unique web interface that allows a facility manager
to monitor multiple inverters at the same time as
Pure sine wave inverters provide cleaner, utility well as set alarms and automatic notifications.  The
grade power than modified sine wave models and system also conducts and records data related to the
work better with LED drivers.  In addition, pure regular monthly tests required by code.
sine wave models have a high surge capacity which
means they are able to exceed their rated wattage
for a limited time to meet the high inrush currents
of LEDs.
“When electrical engineers face tight deadlines to
design emergency lighting systems so a building
or facility can be opened for use, partnering with
a vendor that offers comprehensive options can
“When utility power is lost and the current influx streamline the process,” concludes Lynch.  “In this
from LED fixtures is drawn from an inverter, most regard, some domestic manufacturers can provide a
standard inverters are not able to handle the inrush fully integrated system with as little as two weeks of
even when they are rated for the total rated load,” lead time.”
says Lynch.
For more information, contact Isolite Corpora-
To accommodate such challenges, the company tion at 31 Waterloo Avenue, Berwyn, PA 19312;
offers a variety of units.  This includes units incor- call 800-888-5483; or visit them on the web at
porating pure sine wave technology as well as units www.isolite.com
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