Generac Power Systems 940-2, 941-2 service manual Compensating For Restrictions, Inverter Location

Section 5.2

ENGINE COOLING SYSTEM

Figure 3 — Suspended Mount Inlet Door

Figure 4. Ductwork

Figure 5 — Air Inlet in Vehicle Skirt

COMPENSATING FOR RESTRICTIONS

Such materials as screening, louvers, or expanded metal can restrict the free flow of air. Compensate for this restriction by making the actual air opening pro- portionately larger.

Some materials may offer only a 60 percent “free air inlet area.” Other more efficient materials may provide up to a 90 percent free air inlet area. The percentage of free air inlet opening is usually available from the material supplier or manufacturer.

TO DETERMINE THE ACTUAL AIR INLET OPEN- ING SIZE REQUIRED, DIVIDE 40 SQUARE INCHES BY THE PERCENTAGE OF FREE AIR INLET AREA FOR THE MATERIAL YOU WILL USE.

For example: If you plan to use screening with an 80% free air inlet area, divide 40 by 0.8, which results in 50 square inches. Minimum actual size of air inlet opening in this case is 50 square inches. An opening that measures 4 inches wide by 12-1/2 inches long provides the required air flow (4 x 12.5 = 50 square inches).

INVERTER LOCATION

In order for the inverter to work effectively, it should be located in a dry, well ventilated area. Approximately eight inches of space should be allowed at each end of the inverter for adequate ven- tilation.

The sensing harnesses supplied with the inverter have a maximum length of 12 feet. If the cables are longer than needed, coil the excess near the inverter unit. If a greater length is needed, contact Generac.

DO NOT ATTEMPT TO SHORTEN OR LENGTHEN THE SUPPLIED sensing harnesses. The DC power wires may be cut to the required length. Allow enough length to make connection. Coil excess inside J-Box.

CAUTION: Do not install the inverter in the

!engine compartment. Overheating may result.

TESTING THE INSTALLATION

Generac recommends testing the installation to be sure adequate cooling air flow is available to the unit before placing the unit into service. If the unit shows signs of overheating, you will need to enlarge the air openings. Never place a unit into service until absolutely certain that cooling and ven- tilation is adequate.

IMPORTANT: YOU MUST TEST THE INSTALLA- TION ESPECIALLY IF YOU BRING IN AIR FROM BELOW THE GENERATOR SET.

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