Guardian Technologies 4758, 4456 Engine Startup And Running, Section, Operational Analysis, Part

SECTION 4.2

OPERATIONAL ANALYSIS

PART 4

DC CONTROL

ENGINE STARTUP AND RUNNING

With the fuel solenoid open and ignition occurring, the engine starts. Engine startup and running may be briefly described as follows:

An AC voltage/frequency signal is delivered to the circuit board from the generator engine run winding, via Wire 66A. When AC frequency reaches approximately 30 Hz, the circuit board (a) terminates cranking, and (b) turns on an "engine warm-up timer".

The "engine warm-up timer" will run for about 15 seconds. When this timer finishes timing, board action will initiate transfer to the "Standby" power source. As shown in Figure 4 (above), the timer is still running and transfer has not yet occurred.

Generator AC output is available to transfer switch terminal lugs E1/E2 and to the normally open contacts of a transfer relay. However, the transfer relay is de-energized and its contacts are open.

Figure 4. Circuit Condition - Engine Startup and Running

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