Total Circuit Isolation Method; Grounding The Generator; Generator Ac Neutral Connections; Transfer Switch Start Signal Connections - Generac Power Systems 004812-3 Owner's Manual

• It must have an ampere rating equal to, or greater
than, the total amperage rating of the emergency
distribution panel circuit.
• Have it installed between the building's main dis-
tribution panel and the emergency distribution
panel.
2.4 TOTAL CIRCUIT ISOLATION
METHOD
When a generator capable of powering all electrical
loads in the circuit is to be installed, use the "Total
Circuit Isolation Method." It is possible for the gen-
erator to be overloaded when this isolation method is
employed. The following apply to the transfer switch
in this type of system.
• Ampere rating of the transfer switch must equal
to or greater than the ampere rating of the normal
incoming utility service.
• The transfer switch is installed between the util-
ity service entrance and the building distribution
panel.
2.5

GROUNDING THE GENERATOR

The National Electrical Code requires the frame and
external electrically conductive parts of this equip-
ment to be properly connected to an approved earth
ground and/or grounding rods. For that purpose, a
GROUND LUG (Figure 2.2) is provided on the gen-
erator mounting base. Consult a qualified electrician
for grounding requirements in the area. Grounding
procedures must meet local regulations.
DANGER

Do not connect the ground wire to any pipe
that carries a flammable or explosive substance
– FIRE or an EXPLOSION may result.
Figure 2.2 – Generator Grounding Lug (typical)
Section 2 – Installation
Standby Generator Sets
Proper grounding helps protect personnel against
electrical shock in the event of a ground fault condi-
tion in the generator or in connected electrical devic-
es. In addition, grounding helps dissipate static elec-
tricity that often builds up in ungrounded devices.
2.6 GENERATOR AC NEUTRAL
CONNECTIONS
The manufacturer uses an UNGROUNDED AC neu-
tral. Grounding is recommended only at the main
service entrance. If the neutral wire is grounded and
one of the phase loads becomes grounded, the exces-
sive current opens the load circuit breaker or col-
lapses the generator field. The actual result depends
on the electrical characteristics of the particular
installed generator.
2.7 TRANSFER SWITCH START SIGNAL
CONNECTIONS
If the generator is to be installed with an automatic
transfer switch, such as a GTS-type switch, it is nec-
essary to connect the two-wire start control system.
Connect the two-wire start signal from the automatic
transfer switch to the automatic start connection,
which is located in the upper center of the AC connec-
tion panel (see Figure 2.3). Match wires 178 and 183
in the transfer switch to 178 and 183 on the terminal
strip in the connection box. The conductors for the
two-wire start circuit must be in their own conduit.
Figure 2.3 – Start Signal Connections
Automatic Start Connection (Wires 178 and 183)
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