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IB140024EN
For more information visit: www.eaton.com
Instruction Booklet
Effective: October 2014
Page
7
ATC-300/900 40-400A (480/600Vac)
3-Postion Contactor Based Transfer Switch
Section 3: Equipment Description
3.1 General
The ATS consists of three basic panels:
1. The power panel;
2. The voltage selection and transformer panel (if required); and
3. The microprocessor-based logic panel.
These panels are interconnected via connector plugs and
mounted in an enclosure (Figure 5).
POWER PANEL
LOGIC PANEL
VOLTAGE SELECTION
AND TRANSFORMER PANEL
Figure 5. Three Basic Panels of the ATS (40-400A).
3.2 Power Panel
The power panel is used for making load, power, and neutral con-
nections. The power contactor is mounted on a steel baseplate
(Figure 6).
3.2.1 Main Contacts
This ATS incorporates a power contactor. The main contacts
connect and disconnect the load to and from the different power
sources. The power contactor is mechanically and electrically
interlocked to prevent the two sets of main contacts from being
closed simultaneously.
Figure 6. Typical Power Panel for 40-400A Models.
3.3 Voltage Selection
3.3.1 Standard Voltage Selection (208, 240, 480, 600,
60 Hz and 220, 380, 415, 50 Hz.)
The Standard voltage selection panel consists of multi-tap trans-
formers, contained in a steel case mounted in the enclosure (Fig-
ure 7). The voltage is selected by simply removing the wires from
the default primary taps of both transformers and installing them
on the primary taps for the desired voltage. Taps are provided
for 208 to 600 Vac to satisfy application voltage. The factory
default position is 600 Vac.
CAUTION
WHEN CHANGING THE SELECTED VOLTAGE, THE POWER MUST
BE REMOVED FROM THE ATS AND THE WIRES MUST BE MOVED
ON THE TAPS OF BOTH TRANSFORMERS.