IB01602078E
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Instruction Booklet
Effective: September 2011
Page
19
40-400A (480/600Vac) ATC-300+ 3-Postion
Contactor Based Transfer Switch
4.7 Voltage Selection Adjustments
Certain devices, such as the Voltage Selection Panel, sensing
relays, and timers, need to be set and/or calibrated prior to plac-
ing the ATS equipment in service. Adjustments for logic devices
are described in the separate instructional document dedicated to
the specific logic being used. Voltage selection adjustments are
described in this section.
CAUTION
BE SURE THAT THE CORRECT VOLTAGE IS SELECTED TO MATCH
THE SYSTEM VOLTAGE. AN IMPROPER SELECTION AND/OR CON-
NECTION COULD RESULT IN EQUIPMENT DAMAGE.
4.7.1 Standard
Voltage Selection
Panels (208, 240, 480,
600 V, - 60 Hz & 220, 380, 415 V, -50
Hz)
The Standard voltage selection panel consists of multi-tap trans-
formers, contained in a steel case mounted in the enclosure. To
change the voltage from the factory default 600 Vac, follow the
steps detailed below.
Step1:
Loosen the six screws securing the cover of the Voltage
Selection Transformer case. Slide the cover up, then
away from the case.
Step 2:
Remove the wires from the primary taps of both trans-
formers and installed them on the taps for the desired
voltage (Figure 13B). Note that only one wire per trans-
former is moved since the second wire is the zero refer-
ence.
CAUTION
WHEN CHANGING THE VOLTAGE, ONE WIRE MUST BE MOVED ON
THE PRIMARY TAPS OF BOTH TRANSFORMERS.
Figure 13A. Standard Voltage Selection Panel.
Figure 13B. Standard Voltage Selection Panel.
Figure 13.
Step 3:
Reinstall the cover and tighten the four screws.
