I.B. ATS-AG03
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Effective 7/00
To manually operate the transfer switch, the operating
handle is ratcheted until the desired switch position is
indicated on the indicator wheel. The operating handle,
no matter what design or type of switch operation, is
always electrically "dead" and the indicator wheel free-
wheels should a particular switch have a motor and be
capable of electrical operation. This feature ensures no
operator problems should the switch automatically oper-
ate while the manual handle is being used.
5.3 MANUAL OPERATION (30-200A)
To operate the switch manually, remove the pivot bolt
(located between the two switches (Figure 4-2) using a
5/8-inch wrench or socket. Lift the lever off the two
switches (Figure 5-4), which can then be operated man-
ually (Figure 5-5). The switches are mechanically inter-
locked so that only one can be in the ON position at any
one time, but both can be in the OFF position at the
same time.
5.4 AUTOMATIC TRANSFER
The operating sequence of an automatic transfer switch
is dictated by the switch's standard features and select-
ed options. Operation of an automatic transfer switch
during normal source failure and normal source restora-
tion will be described here with only standard options
included on the switch. Additional options, as described
in Section 3, can change sequences and timing,
depending upon the options selected. Become familiar
with additional options selected and their effect on the
normal operation of an automatic transfer switch.
5.4.1 NORMAL POWER SOURCE FAILURE
Standard normal source failure is defined as a reduction
or loss of voltage. If this occurs, the sequence of opera-
tion is as follows:
• Failure of the normal source is detected by the micro-
processor intelligence.
• When the microprocessor detects a failure, the normal
relay drops out, opening certain contacts while closing
others. One of the contacts starts the engine-driven
generator.
• When the emergency source voltage reaches its oper-
ation rating, an emergency relay closes, starting the
transfer operation. This operating sequence opens the
normal switch and closes the emergency switch.
• The load is now transferred to emergency source.
Figure 5-3 Indicator Wheel in Neutral Position (300-
600A Models)
Figure 5-4 Transfer Mechanism with Lever Removed
(30-200A Model)
