2�2 Theory Of Operation; Figure 2 - 2-Pole From A 3-Phase Supply - Alpha Technologies AMPS HP2 Power System Installation & Operation Manual

120/208Vac 3-Phase
Each phase conductor is 120 degrees out of phase with the other, as shown in Figure 2. All three phases (3-pole)
plus the neutral are in use.
2.2 Theory of Operation
Each AMPS module includes a reliable 48Vdc to 120Vac inverter as well as an AC-to-DC converter. When AC
Mains is available, AC power is converted to a high voltage DC bus, which is then converted back to AC. In this
high performance (HP) mode, AMPS delivers fully conditioned, line-regulated telecom-grade AC power with 94%
system efficiency.
AC
Mains
DC In
CAN bus external
communication
When AC Mains is unavailable, DC battery power is converted to AC with zero transfer time. An intelligent high
voltage DC bus decides when to draw power, and how much power to draw, from AC or DC source. During AC
input brownout condition, output power is supplemented by battery power.
AC to DC input transfer can also be automatically triggered via the system controller to enable advanced opera-
tion such as utility peak shaving.
In case of a fault, advanced DSP controls allow the AMPS module to isolate itself, while the rest of the system
continues to power the load (with reduced output).
0260080-J0 Rev D
208V
Figure 2 — 2-Pole from a 3-phase supply
DSP
N
Dual redundant
communication and
synchronization
between modules
L1
208V
L2
208V
L3
Telecom Grade
AC Output
11