Eaton EGS Series User Manual

3
Instruction Booklet IB0162064EN
Effective January 2014
O & M Manual for the EGS Service
Entrance Automatic Transfer Switch
Eaton Corporation www.eatoncanada.ca
1.2 General Information
ATSs are used to protect critical electrical loads against loss of
power. The load’s utility power source is backed up by a generator
power source. An ATS is connected to both the utility and generator
power sources and supplies the load with power from one of these
two sources. In the event that power is lost from the utility power
source, the ATS transfers the load to the generator power source.
Once the utility power is restored, the load is automatically trans-
ferred back to the utility power source (Figure 2).
Figure 2. Typical Load Transfer Switch (Contactor) Schematic.
An intelligence system initiates the transfer when the utility power
source fails or falls below a preset voltage. An engine start is then
initiated by the ATS or the generator and the ATS transfers to the
generator power source when sufficient generator voltage is avail-
able. When the utility power source is restored, the ATS automati-
cally transfers back and the generator will shut down after a time
delay. In the event the utility power source fails and the generator
power source does not appear, the ATS remains connected to the
utility power source until the generator power source does appear.
Conversely, if connected to the generator power source and the
generator power source fails while the utility power source is still
unavailable, the ATS remains connected to the generator power
source.
ATSs automatically perform the transfer function, and include three
basic elements.
1. Main contacts to connect and disconnect the load to and from
the source of power.
2. Solenoids to make the transfer of the main contacts from source
to source.
3. Intelligence/supervisory circuits to constantly monitor the condi-
tion of the power sources and thus provide the intelligence nec-
essary for the switch and related circuit operation.
Utility
Generator
Load
1.2.1 Design Configuration
The Eaton Service Entrance Rated, Automatic Transfer Switch is
a rugged, compact design that combines a service entrance rated
disconnect, and ATS all in a single enclosure. The design provides
for top entry service cabling from the meter socket. A factory
wired 100 or 200A circuit breaker provides a Canadian approved
service entrance rated disconnect means. The ATS is controlled by
an Eaton RTC-100 controller or relay, and utilizes power contactors
to transfer essential loads from one power source to another
(see Figure 3). The switch’s design uses suitable mechanical and
electrical interlock switches to eliminate the possibility of connecting
the utility service to the generator output. In addition, a manual
override lever is provided for the transfer function.
WARNING
DO NOT MANUALLY TRANSFER THE SWITCH WHILE UNDER LOAD.
Figure 3. EGSCA200ASE (200 A).

Eaton EGS Series Specifications

General

Brand	Eaton
Model	EGS Series
Category	Switch
Language	English