Guardian Technologies 4759, 4456 Utility Source Voltage Available, Utility Source Power Available

V-TYPE PREPACKAGED TRANSFER SWITCHES

PART 3

SECTION 3.2

OPERATIONAL ANALYSIS

UTILITY SOURCE VOLTAGE AVAILABLE

Figure 2 is a schematic representation of the transfer switch with utility source power available. The circuit condition may be briefly described as follows:

❏Utility source voltage is available to terminal lugs N1 and N2 of the transfer mechanism, transfer switch is in the UTILITY position and source voltage is available to T1, T2 and customer load.

❏Utility source voltage is available to limit switch (XA1) via the normally-closed transfer relay contacts (1 and 7) and Wire 126. However, XA1 is open and the Circuit to the utility closing coil is open.

❏Utility voltage "sensing" signals are delivered to a circuit board on the generator, via Wire N1A, a 5 amp fuse (F1), transfer switch terminal N1, generator terminal N1 and a sensing transformer. The second line of the utility voltage "sensing" circuit is via Wire N2A, a 5 amp Fuse (F2), transfer switch terminal N2, generator terminal N2, and the sensing transformer.

Figure 2. Utility Source Power Available

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