IB140015EN
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Instructional Booklet
Effective: August 2014
Page
13
ATC-900 Magnum Tranfer Switch O & M Manual
3.2.5 Drawout Mechanism
The drawout mechanism is described in detail in Section 6
(Figure 14).
Figure 14. Drawout Mechanism (Closed Transition Shown)
3.3 Voltage Selection Panel
3.3.1 Voltage Selection Connectors (208, 220, 240, 380, 415,
480, and 600 Vac, 50/60 Hz)
The voltage selection panel consists of multi-tap transformers,
contained in a steel case mounted in the transfer switch enclosure
(Figure 15). It is mounted at the bottom panel of the switch. The
cover has “teardrop” holes for the screws to allow easy access to
the transformers. The voltage is selected by simply removing the
connector and reconnecting to the desired voltage. (The ATC-
900) setpoints will have to be changed to the voltage selected). If
the connectors are not on the outside, the switch is older than
November of 2014. Taps are available to switch out, see section
4.6 for instructions. Taps are provided for 208, 240, 480, 600 for
North America and 220, 380, 415 for International voltages. Fig-
ure 16 shows the two transformers inside the enclosure Line
Replaceable Unit (LRU), one for Source 1 and the other for Source
2, Vac to satisfy most voltage requirements. The factory default
position is the voltage tap based on customer voltage specifica-
tion.
Figure 15. Voltage Selection Panel
Figure 16.Power Transformers (Source1 & Source 2).
3.4 Logic Panel
The logic panel provides the intelligence and supervisory circuits
which constantly monitor the condition of both the Source 1 and
Source 2 power sources, thus providing the required intelligence
for transfer operations (Figure 17). Detailed information is pre-
sented in a separate document:
•
ATC-900 Instruction Book IB140012EN
WARNING
WHEN CHANGING THE SELECTED VOLTAGE, THE POWER MUST BE
REMOVED FROM THE TRANSFER SWITCH AND THE WIRES MUST
BE MOVED ON THE TAPS OF BOTH TRANSFORMERS.
