460-480 Tyco Electronics, 460-480 Datasheet - Page 111

• Manufacturer Part Number: 460-480
• Description: Voltage Transformer
• Manufacturer: Tyco Electronics
• Series: 460r

Specifications of 460-480

• Turns Ratio: 4
• Transformer Mounting: Chassis
• Voltage Ratio: 480
• Primary Voltages: 480V
• Power Rating: 150VA
• Output Voltage: 120V
• Mounting Type: Foot Mounted
• Transformer Type: Voltage
• Lead Free Status / RoHS Status: na

Voltage Transformer Fuses
This Voltage Transformer section contains some models that can be fitted with primary
fuses. The fuse style is the CC class having a rejection feature. These fuses are rated as
current limiting with a 200,000 ampere (RMS symmetrical) interrupting rating, for
BRANCH circuits of 600 Volts or less. The fuses are contained in a fuseblock that will
accept only class CC, UL approved fuses. This prevents other fuse types of the same size
being fitted that would have a lower interrupting capacity and/or a non-current limiting
capability. It is possible to fit the fuse carrier and fuseblock to our models 450, 456 and
475 after manufacture so that a field retro-fit can be made.
The National Electric Code requires that all voltage transformers installed indoors or in an
enclosure shall be fused in the primary circuit with devices rated 15 amperes or less. This
arrangement will protect the supply from faults internally in the transformer, but faults in
the secondary circuit may not rupture the primary fuse. It is suggested that the user fit
secondary circuit fuses to protect the transformer from such faults. The recommended
fuse rating is 125% of rated full load amperes, with a maximum of 167%, again referring to
the National Electric Code.
When fusing either the primary or the secondary circuits of voltage transformers that are
connected line-to-ground, only one fuse should be fitted line side so that the transformer
cannot remain energised from a line connection while the grounded neutral fuse is
ruptured. The selection of fuses as listed with each model that can accept fuses, is based
upon magnetising inrush considerations and not necessarily upon the VA rating of the
transformer. In cases where the user wishes to select and mount fuses elsewhere in
equipment, we recommend that the ratings given be adhered to. If no fuses are listed,
consult the factory engineers for a recommendation.
Voltage Transformer Burden Date
Burden
W
X
M
Y
Z
ZZ
Volt Amperes
12.5
25
35
75
200
400
Power Factor
0.10
0.70
0.20
0.85
0.85
0.85
84.3°
45.6°
78.5°
P.F. Angle
31.8°
31.8°
31.8°
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