10
016-564-B0-001, Rev. A1 (05/2022)
1.0 Overview and Specifications, continued
1.2 Alpha
®
APX3-G Series Specifications
1.3 Operating Principle
The APX3-G Series non-standby power supply utilizes ferroresonant transformer technology to provide line conditioning
and voltage regulation. The primary and secondary windings of the transformer are physically isolated from each other by
a large steel core which significantly reduces the capacitive coupling of spikes and noise to the secondary winding. This
provides a regulated, current-limited output with excellent isolation and noise attenuation: 140dB common mode; 80dB
transverse mode.
An oil-filled resonant AC capacitor is connected to the resonant (secondary) winding of the transformer forming a
tank
circuit
. This provides the resonant circuit function which contributes to the voltage regulation of the supply. The advantage
of this type of transformer/capacitor design is the ability of the ferroresonant transformer to regulate its output voltage
over a wide range of input voltages and output loading. Typical output voltages may vary
+
5% with 87% efficiency, with
input voltage variations of
+
20% of nominal line voltage, and output loading of 20% to 100%. This tight regulation is
advantageous in cable television applications as the active devices are protected from dangerous voltage fluctuations.
Another unique feature of the ferroresonant transformer is its ability to provide current limiting in the event of a short-
circuit. This effect is called
foldback
. The transformer’s output current can typically reach 150% of the nameplate output
current rating for a short period of time without damage to the transformer. When the transformer reaches the saturation
point, the output current will decrease (foldback on itself) to a minimum value, and thereby provide current limiting.
Designs based on a ferroresonant transformer are extremely rugged and reliable, and offer many years of trouble-free
operation.
Alpha
®
non-standby power supplies are extremely efficient, and have a typical efficiency rating of >87% at full load.
Model
Input Voltage
Frequency
Output Voltage
Max. Output Current
608G
176 - 276VAC
50Hz ±3%
59.9 - 66.2VAC / 45.6 - 50.4VAC
8A
615G
176 - 276VAC
50Hz ±3%
59.0 - 66.2VAC / 45.6 - 50.4VAC
15A
Environmental Specifications
Operating temperature range (Standard Outdoor)
Agency compliance: -40°C to 40°C
Design limit: -40°C to 50°C
Operating temperature range (Vented Indoor)
Agency compliance: -40°C to 55°C
Design limit: -40°C to 60°C
Humidity rating
95% (non-condensing)
Mechanical Specifications
Weight
Audible Noise
(Standard Outdoor Configuration)
Audible Noise
(Vented Indoor
Configuration)
Model 608G (Standard)
12.5kg
<45dBA
Model 608G (Mesh)
12.2kg
<43dBA
Model 615G (Standard)
15.0kg
<45dBA
Model 615G (Mesh)
14.7kg
<43dBA
Dimensions, overall (H × W × D)
333mm × 170mm × 240mm
An optional mesh cover is available for all models. Units supplied with mesh covers are intended
for indoor use only. Contact your Alpha
®
representative for details.
NOTICE
:
The APX3-G unit must ship palletized at all times.
NOTICE
:
Table 1-1, APX3-G Series Specifications