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IB70-8671
Instructional Booklet
Page
10
Effective: July 2008
O & M Manual for the EGS AutomaticTransfer Switch
with RTC-50 Control and Integral Loadcenter - 100 Amp
4.5 Wiring
4.6 Installation
In a typical installation for critical loads (see Figure 10), the ATS
(1) and the generator (2) are connected to the power supply. The
ATS and emergency distribution panel (1) receive utility power
from a dedicated breaker in the utility service panel (3). The ATS
and emergency panel receive generator power from the generator
(2). Power from the utility feeds the utility panel.
Figure 10. Typical Installation of a Residential ATS.
The ATS (1) and generator (2) are connected to the power supply.
The automatic transfer switch is located between the generator
and the utility panel (3).
When the utility power fails, the ATS will sense the failure, the
generator will start, and when sufficient generator voltage is avail-
able, the ATS will switch all loads to the emergency panel. All
emergency loads will receive power from the generator. A line
breaker is required between the generator power source and the
transfer switch (see Figure 11). When utility power returns, the
ATS will switch all power back to the utility panel and the genera-
tor will shut down.
Figure 11. Diagram of a Typical Installation (Critical Loads Only).
4.7 Generator Utility Sensing Connection
The generator utility sensing connections are located on the fuse
block that is installed at the bottom of the power panel. The utility
sensing wires, required for proper generator operation, are con-
nected at this point.
Note:
Prior to making the generator utility sensing connection to the ATS,
set the generator control selector switch to the OFF position to prevent an
unwanted generator start. Control wiring, such as the generator utility
sensing wires, must be run separately from the power cables.
Use the proper wire size as listed by the generator set (Genset)
manufacturer.
This ATS is intended for use on generators with built in auto start
features. These generators sense, and react to, utility power.
Remote starting contacts are not provided in this transfer switch.
WARNING
POWER CONDUCTORS AND CONTROL WIRING MAY HAVE VOLT-
AGE PRESENT THAT CAN CAUSE SEVERE PERSONAL INJURY OR
DEATH. DE-ENERGIZE ALL POWER OR CONTROL CIRCUIT CONDUC-
TORS BEFORE BEGINNING TO PERFORM ANY WIRING ACTIVITY TO
OR WITHIN THE ATS EQUIPMENT.
CAUTION
CHECK THE ATS EQUIPMENT NAMEPLATE FOR RATED VOLTAGE.
IT SHOULD BE THE SAME AS THE UTILITY AND GENERATOR LINE
VOLTAGES. OPERATING THE EQUIPMENT ON IMPROPER VOLTAGE
CAN CAUSE EQUIPMENT DAMAGE.
Generator
(Source 2)
Circuit Breaker
(typically included
in Genset)
E
Di t ib ti
P
l
Critical
Loads
Utility
(Source 1)
Watt-Hour
Meter
Non-Critical
Loads
Utility Panel
Transfer
Switch
