Megapoxy E is a two-part epoxy casting system for insulating and protecting instrument transformers, lighting transformers, power transformers, coils and electrical switchgear components. Two hardener options let you choose the working time and temperature performance that suit the electrical assembly.
Hardener E uses a 3:1 mix by volume, provides 60 minutes of working time at 25°C and is suited to operating temperatures up to 80°C. Hardener 155 (E155) uses a 6:1 mix by volume, provides 30 minutes of working time and is the higher-temperature option for service up to 150°C. Both require a minimum 24-hour cure at 25°C.
Choose E when encapsulating transformers or switchgear that need the Hardener E or E155 temperature options. Megapoxy 34 is a lower-viscosity casting resin for electrical cable joints and component potting, with a 4:3 mixing ratio.
Clean and dry the casting cavity and components before mixing. Measure against the selected hardener: E at 3:1 by volume or E155 at 6:1. Pour carefully to limit trapped air and allow at least 24 hours to cure at 25°C. Do not interchange the two hardener ratios.
What's the difference between Megapoxy E and E155?
Standard E uses Hardener E at 3:1 by volume with 60 minutes of work time and an 80°C operating rating. E155 uses Hardener 155 at 6:1 with 30 minutes of work time and a 150°C operating rating.
Can Megapoxy E encapsulate transformer coils?
Yes. It is made for transformers, coils, electrical switchgear and similar electrical casting applications.
How long does electrical casting epoxy E need to cure?
Both hardener systems have a minimum 24-hour cure at 25°C. Ensure the selected formulation is suitable for the assembly's electrical and thermal service conditions.
| Property | Value |
|---|---|
| Mixing Ratio by Weight Resin (Hardener E) | 5 |
| Mixing Ratio by Weight Hardener (Hardener E) | 1 |
| Mixing Ratio by Volume Resin (Hardener E) | 3 |
| Mixing Ratio by Volume Hardener (Hardener E) | 1 |
| Density Mixed (Hardener E) | 1.55 g/cm3 |
| Working Time at 25°C (Hardener E) | 60 Minutes |
| Minimum Curing Time at 25°C (Hardener E) | 24 Hours |
| Viscosity Part A | 10000 - 15000 cps |
| Viscosity Part B (Hardener E) | 500 - 900 cps |
| Mixed Viscosity (Hardener E) | 3000 cps |
| Specific Gravity Part A | 1.65 - 1.75 |
| Specific Gravity Part B (Hardener E) | 0.95 - 0.97 |
| Mixed Specific Gravity (Hardener E) | 1.55 |
| Ultimate Compressive Strength (Hardener E) | 80 MPa |
| Martins Heat Distortion Temperature (Hardener E) | 65°C |
| Typical Dielectric Strength 50Hz, 25°C (Hardener E) | 18 KV/mm |
| Bond Strength | 20 MPa |
| Shore D Hardness | 75 |
| Mixing Ratio by Weight Resin (Hardener 155) | 10 |
| Mixing Ratio by Weight Hardener (Hardener 155) | 1 |
| Mixing Ratio by Volume Resin (Hardener 155) | 6 |
| Mixing Ratio by Volume Hardener (Hardener 155) | 1 |
| Density Mixed (Hardener 155) | 1.6 g/cm3 |
| Working Time at 25°C (Hardener 155) | 30 Minutes |
| Minimum Curing Time at 25°C (Hardener 155) | 24 Hours |
| Viscosity Part B (Hardener 155) | 18 - 24 cps |
| Specific Gravity Part B (Hardener 155) | 0.90 - 0.95 |
| VOC Content | Nil |
| Density | 1.55 |
| Ultimate Compressive Strength (Hardener 155) | 100 MPa |
| Typical Dielectric Strength 50Hz, 25°C (Hardener 155) | 19 kV/mm |
| Maximum Service Temperature (Hardener E) | 80°C |
| Maximum Service Temperature (Hardener 155) | 150°C |
Here are some common examples on where Megapoxy E used by our customers.
