Acme Catalog

169 / 244

169
toll free 800.334.5214 ACME ELECTRIC |
A m v e c o T o r o i d a l S o l u t i o n s
OVERALL COMPARISON OF 250VA E-I CORE ISOLATION TRANSFORMER VS. 250 VA TOROIDAL ISOLATION TRANSFORMER
Feature 250VA E-I Core Transformer 250VA Toroid Transformer
Height 4.7" (119mm) 2.2" (56mm)
Width 3.9" (99mm) 4.5" (114mm)
Depth 4.3" (109mm) 4.5" (114mm)
Volume 78.8 . (508.4cm2) 35.0 . (225.8cm2)
Weight 10 lbs. (4.5 kg) 5 lbs. (2.3 kg)
Mounting Requirements Four corner bolts Sinle bolt through center
No Load Losses 10.0 W 1.5 W
Continuity of Magnetic Path 50% of grain perpendicular 100% parallel grain orientation
Air Gaps Approximately 180 (60 laminations x 3) None
Magnetic Properties of Core Affected by clamping, welding, banding, etc. Optimized prior to winding and remains stable
Coupling Factor Limited by bobbin width and layers of windings Maximized by even winding distribution and close proximity to core
Primary to Secondary Insulation
Polyester film-Class B (130˚C)
Four layers minimum between windings
Meets test requirement of 4000V RMS for
1 minute between primary and secondary
Windings
Base coat of Polyester. Heavy
topcoat of amide imide (200˚C)
Wound uniformly over entire core
Better heat dissipation
Windings configured for minimum
flux leakage
Low voltage maintained between
adjacent turns
Core Insulation
All cores: 100% surface coverage of four layers
of 2 mil polyester film Class B (130˚C)
Protects, insulates and cushions the core from
windings and reduces vibration
Core
Cores are manufactured and annealed
in-house, under controlled conditions
Continuous tightly wound grain oriented
silicon steel...no airgaps, no mechanical
noise
Lathed radial corners... compact design,
most efficient use of materials
No core caps necessary
Outer Insulation
Tape wound type: Standard two layers
polyester film Class B (130˚C)
Magnetic enclosures optional