Guardian Technologies 4390, 4456, 4389 Initial Dropout Of Utility Source Voltage, Section, Part

SECTION 4.2

OPERATIONAL ANALYSIS

PART 4

DC CONTROL

INITIAL DROPOUT OF

UTILITY SOURCE VOLTAGE

Refer to Figure 2, above. Should a "Utility" power source failure occur, circuit condition may be briefly described as follows:

The circuit board constantly senses for an acceptable "Utility" source voltage, via transfer switch fuses F1/F2, transfer switch "Utility 1/Utility 2" terminals, connected wiring, control panel "Utility 1/Utility 2" terminals, the sensing transformer (TX), and Wires 224/225.

Should "Utility" voltage drop below approximately 60 percent of the nominal source voltage, a 15-second timer on the circuit board will turn on.

In Figure 2, the 15-second timer is still timing and engine cranking has not yet begun.

The AUTO-OFF-MANUAL switch is shown in its AUTO position. Battery voltage is available to the circuit board, via Wire 13, 15 amp fuse (F1), Wire 15, the AUTO-OFF-MANUAL switch (SW1), Wire 15A, and Pin 10 of the circuit board connector.

Figure 2. Circuit Condition -

Initial Dropout of Utility Source Voltage

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