Section 2 — Installation
Centurion
Figure 2.1 – Basic Standby Electric System
2.6TOTAL 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 generator 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 be equal to, or greater than, the ampere rating of the normal incoming utility service.
•The transfer switch is installed between the utility service entrance and the building distribution panel.
NOTE:
Generac recommends the use of a Generac Power Systems transfer switch in conjunction with this generator.
2.5EMERGENCY CIRCUIT ISOLATION
METHOD
This prevents overloading the generator by keeping electrical loads below the wattage/amperage capacity of the generator. If the generator is powering only critical loads, within the wattage/amperage capacity, during utility power outages, consider using the emergency circuit isolation method.
Critical electrical loads are grouped together and wired into a separate “Emergency Distribution Panel.” Load circuits powered by that panel are within the wattage/amperage capacity of the generator set. When this method is used, it is difficult to overload the generator. The transfer switch must meet the following requirements:
•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 distribution panel and the emergency distribution panel.
2.7GROUNDING THE GENERATOR
The National Electrical Code requires the frame and external electrically conductive parts of this equipment 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 generator 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.
Proper grounding helps protect personnel against electrical shock in the event of a ground fault condition in the generator or in connected electrical devices. In addition, grounding helps dissipate static electricity that often builds up in ungrounded devices.
Figure 2.2 – Generator Grounding Lug (typical)
10 Generac® Power Systems, Inc.
