ELAUTOTRNSSW-SA Electrical, Auto Transfer Switch - Semiannual

Application:                                                Man Hours 1.5

This applies to those devices utilized to automatically switch an
electrical power supply from it's normal source to an alternate or emergency
source of supply.  These devices are normally associated with emergency power
generators, but they can also be used to transfer from one commercial source to
another.  Multiple devices may be used where Uninterruptible Power Supply (UPS)
systems are installed.

Special Instructions:

1.  Review manufacturer's instructions on operation and maintenance.
2.  Review the switching diagram and the effected electrical systems diagrams.
3.  Verify location of generator, transfer switches, critical load, and effected
4.  Schedule outage with operating personnel and occupant agencies.
5.  All tests shall conform to the appropriate ASTM test procedure and the values
    used as standards shall conform to the manufacturer's and ANSI standards

Items to Check & Initial Completion:

1.___  Check with effected occupant agencies and request that agency determine
       what equipment will be de-energized.
2. ___ Turn automatic transfer switch and generator automatic controls off.  Tag
       control switches.
3. ___ Open and tag supply breaker.
4. ___ Open doors on automatic transfer switch and check phase-to-phase and
       phase-to-ground for presence of voltage.
5. ___ Clean inside of switch cubicle.
6. ___ Tighten all connections, checking for signs of overheating wires.
7. ___ Disconnect wires attached to each phase of the normal supply, that
       supplies power to the under voltage relays.  Test the under voltage
       relays. After testing relays, re-connect wires.
8. ___ Lubricate mechanism bearings, if required.
9. ___ Locate and disconnect operating mechanism control wires and, using a
       source of voltage, operate the mechanism.
10.___ With the mechanism electrically held, use a micro-ohmmeter to check the
       contact resistance.  Make sure the micro-ohmmeter is connected from the
       normal supply cable connection to the critical load cable connection.
       Perform the same test on the emergency source.
11.___ Re-connect the operating mechanism control wires.
12.___ Clean indicating lenses and change lamps as needed.
13.___ Restore the transfer switch to normal position.
14.___ Check with affected occupant agencies for generator
15.___ Remove tags and energize normal supply breaker, picking up the critical
16.___ Remove tags and place generator controls in the automatic position.
17.___ Open normal power breaker; the generator should start and the transfer
       switch should transfer the critical load.
18.___ Close the normal power breaker; the transfer switch should transfer the
       load and the generator should shut down after a cool down period.
19.___ Check with the effected occupant agencies to see that normal services have
       been restored to all areas.

Tools and Materials:

1.  Standard Tool kit.
    Plus  Insulated pliers and screwdrivers
          Wire strippers
          Wire crimpers
          Voltmeter - Ohmmeter - Milliammeter
          Clamp on meter(volt - ohm - amp meter)
          Soldering kit
          1/8" 25' fish tape
          Burnishing tool
2.  Micro-ohmmeter
3.  Variable AC voltage source (test cable)
4.  AC and DC voltmeter
5.  Cleaning equipment and materials

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