Technical Notes
For Manufacture of Toroidal Transformers

Material Notes

Core caps
Polypropylene caps with a wall thickness of 1mm Maximum operating temperature 160deg.C

Copper wire
Enamelled copper wire Polyester / Imide Grade 2
Temperature index 180degC Thermal Class H

Insulation material
Mylar A clear polyester 50 microns thick. Maximum operating temperature 160deg.C

Black Polyester is two layers of 23micron thick laminated together using an adhesive with black pigment. This has the benefit that the black will not scratch off.

Although the film has UL approval the laminated product does not.

PVC Sleeving
Manufactured to BS2848/3/105T
Wall thickness 0.5mm operating temperature 105deg.C

Flexible Leads
UL style UL1015 600V 105deg.C
Flammability rating of flexible cables- Vertical wire flames tested - VW-1

Thermal cut-offs
M03 self re setting thermal cut-out 120deg.C Maximum load 4A 250 V, 50-60Hz
Durability 10,000 switching cycles. Contact system Normally closed
VDE approval

M13 self re setting thermal cut-out 120deg.C Maximum load 4A 250 V, 50-60Hz
Durability 10,000 switching cycles. Contact system Normally open
VDE approval

H130 Single shot thermal cut-off 130deg.C Max current rating 2amp 250volt
Approvals UL CSA VDE BEAB
Contact system Normally closed

Terminals
1/4" Spade connectors

Connectors

Molex 2.5mm Pitch connectors
3A 250V ac

Tyco Electronics Mat-N-Lok
Universal power coupling and power to board connections 15A max Voltage rating 600v

Molex Sabre Series
Robust single row connectors for high current applications up to 18A max voltage 1000v

Hardware
Standard hardware comprises of two solid neoprene mounting pads 1.5mm thick and one steel washer with suitable nut and bolt.

Potting Material
Fire retardant Polyurethane potting system. Black, rigid with a high degree of mechanical strength. Shore hardness 85-90
PC 5243 has been tested to UL94 Flammability specification and a V-O classification

Plastic Lighting cans
Nylon 66 Polyamide with 14% glass filler
Continuous working temperature 80deg.C Maximum 160deg.C Melt point 255deg.C
Flammability: Fire retardant UL94

All components U.L. Approved.

Construction notes

Insulation
The insulation system is suitable for 130deg.C maximum operating temperature. Class 130 (B)

Insulation Test 4000vac between primary and secondary

Manufactured In compliance of EN60742, BS3535 Class B 130deg.C
UL 1411 UL Approval file number E188896SP

Running Temperature:
Not more than 60deg.C above ambient

Flexible Leads
Flexible leads connected to the Toroidal transformer winding by solder connection and insulated from windings with polyester film board/polyester adhesive tape/PVC tubing.

Security of Parts
Parts shall be secured to prevent any rotation or shifting, which could result in a reduction of electrical spacing.

Connectors
Connectors shall be applied so as to ensure the insulation and containment of all bare wiring strands.

Testing
All transformers to be tested immediately before packing for:
1. Residual current
2. Open circuit voltage test
3. Hi pot test

Toroidal Transformer Diagram