ABB Zenith ZT30 Operation And Maintenance Manual page 49

Controller Power Supply
(UTA – universal transformer assembly)
System line voltage is transformed to 170Vdc to power the
MX350 controller and 24Vdc ungrounded to power relays
via the universal transformer assembly (UTA). The power
supply is termed "universal" because the same unit handles
all line voltages from 120Vac through 600Vac via an internal
six-position jumper array. Figure S6-23 shows the external
connections points for the UTA. The UTA also features a
120Vac uninterruptible power supply input and 24Vdc input
battery options. 120Vac and 24Vdc (ungrounded) must
be supplied together from an uninterrupted power source.
In addition, test terminals are included for transformer
Zenith Automatic Transfer Switch | new.abb.com/low-voltage 49