Section 1 — Installation
Guardian
1.8EMERGENCY CIRCUIT
ISOLATION METHOD
One effective way of preventing the generator from being overloaded is to use the “Emergency Circuit Isolation Method” (Figure 1.6).
Essential electrical loads are grouped together and wired into a separate emergency distribution panel. Load circuits fed by the emergency distribution panel must be within the unit's rated wattage capacity. The following apply to this type of isolation system:
•The transfer switch is installed between the main and the emergency distribution panels as shown.
•The transfer switch must have an ampere rating equal to the ampere rating of the emergency circuit.
Figure 1.6 – Emergency Circuit Isolation Method
1.9TOTAL CIRCUIT
ISOLATION METHOD
If essential electrical loads cannot be grouped togeth- er and wired into an emergency distribution panel, you will have to select load circuits that the generator will power during a utility power outage.
Be careful to avoid overloading the generator. The fol- lowing apply to the “Total Circuit Isolation Method” (Figure 1.7):
•The transfer switch is installed between the utility service entrance and the distribution panel.
•The transfer switch ampere rating must be equal to the main electrical service entrance rating.
Figure 1.7 – Total Circuit Isolation Method
*Ampere rating must equal or exceed the ampere rating of the emergency distribution system.
**Ampere capacity is not to exceed the alternator rating. Only these items will be powered by the standby alternator. If the electrician sizes the load properly, the alternator cannot be overloaded.
All wiring must conform to the National Electrical Code, and all state and local codes. Consult a quali- fied, licensed electrician.
The above illustration assumes the utility is supply- ing
Service Disconnect
*Ampere rating is equal to or larger than main (nor- mal) power source.
**Use caution with this system to prevent overload of the alternator during utility power failure. All load items in the distribution panel must be individual- ly turned off. Only certain items can be turned back on during alternator operation. These items should be specified by your electrician so as not to overload the alternator.
All wiring must conform to the National Electrical Code, and all state and local codes. Consult a quali- fied, licensed electrician.
The above illustration assumes the utility is supply- ing
Generac® Power Systems, Inc. 11
