CRMagnetics Catalog

130 / 162

130
PTW3-1-60
G
• Primary terminals that are unfused are 1/4-20 brass screws with one flatwasher
and lock washer.
• Primary terminals that are fused are 1/4-20 brass screws with one flatwasher
and lock washer and two nuts.
• Secondary terminals are No. 10-32 brass screws with one flatwasher and
lock washer.
• The core and coil assembly is encased in a plastic enclosure and vacuum
encapsulated in polyurethane resin.
• Thermal burden rating is for 120 volt secondaries.
• Switch gear style is similar to fused style. No fuse or fuse clip is provide, but
inserts for fuse clips are supplied.
FUSE FOR MODEL
PT W3 TRANSFORMER
RATING
VOLTS
INTERRUPTING
AMPERES (SYM)
SUGGESTED
RATING
CONTINUOUS
AMPERES
CAP DIA.
INCHES
(d)
LENGTH
INCHES
CLIP CENTERS
INCHES
2400:120V 5.5kV 45,000 2.0E 1.0 5.63 5.00
3300:110V 5.5kV 45,000 2.0E 1.0 5.63 5.00
4200:120V 5.5kV 45,000 1.0E 1.0 5.63 5.00
4800:120V 5.5kV 45,000 1.0E 1.0 5.63 5.00
(a) Two fuse transformers should not be used for Y connections. It is preferred practice to connect one lead from each voltage transformer directly to the neutral terminal, using a
fuse in the line side of the primary only. By using this connection a transformer can never be made “live” from the line side by reason of a blown fuse in the neutral side. For continuous
operation the transformer primary voltage should not exceed 110% of rated value.
(b) Voltage transformers connected line-to-ground cannot be considered to be grounding transformers and must not be operated with the secondaries in closed delta because
excessive currents may flow in the delta.
(c) Values in table are in ohms.
(d) Fuse clips noted as “CCS” or “CS” accept fuses with 1.0” Dia. caps and 5” clip centers. Fuses clips with a suffix“CCL” or “CL” accept fuses with 1.63 dia. caps and 5.88” clip centers.
Note: It is recommended that system line-to-line voltage not exceed the transformer maximum system voltage level.
UNFUSED ONE FUSE TWO FUSE
The circle diagram can be used to predict the performance of a transformer
for various loads and power factors. A convenient scale of volt-ampere is
shown on the unity power factor line (u.p.f ) and commences at the zero or
no-load locus. To use the diagram, measure the known V.A. and scribe an arc
about the “Zero ” locus of a length that contains the angle of the burden
power factor. The point at which the arc terminates is the error locus in phase
angle minutes and ratio correction factor.
CIRCLE DIAGRAM
RECOMMENDED MINIMUMSPACINGS
A = Unit to Unit or to Ground = 1.00” minimum.
B = HV to Ground in air = 3.00” minimum.
Recommended spacing are for guidance only. User needs to set
appropriate values to assure performance for high potential test,
impulse test, high humidity, partial discharge, high altitude, and other
considerations like configuration.
Potential Transformers
3500 Scarlet Oak Blvd. St. Louis MO USA 63122 V: 636-343-8518 F: 636-343-5119
Web: E-mail:
The Professional
Energy Monitoring
Company
ISO 9001:2008QualityManagementSystem
M N TI