|
Feature |
RIF® Dry type, paperless (Resin Impregnated Fibreglass) |
RIP Dry type, paper (Resin Impregnated Paper) |
OIP Oil-filled. paper (Oil impregnated paper) |
|
Maintenance |
Maintenance-free |
Tan δ and C1 need to be checked regularly. |
Tan δ and C1 need to be checked regularly. DGA testing of the bushing oil should be done on older bushings. Leak mitigation. |
|
Explosion-resistant |
Yes (This has been validated with an internal arcing fault test. Arc fault current = 31.5 kA; arc duration = 150 ms) |
No |
No |
|
Thermal temperature rating of insulation |
130°C A higher thermal margin. |
120°C |
105°C |
|
Optional built-in insulation condition monitoring |
The test tap can also be supplied with an LED sensor that provides visual indication of the real-time condition of the bushing insulation. The built-in circuitry detects any change to the C1 capacitance. LED status lite - GREEN for GOOD and RED for a possible deteriorating condition. |
Not provided |
Not provided |
|
Cost to produce custom design “like for like” replacement bushings |
Low No re-tooling required for custom designs. |
High Expensive re-tooling required for custom designs. Cost and lead time significantly impacted. |
High Expensive re-tooling required for custom designs. Cost and lead time significantly impacted. |
|
Cost of ownership |
Low. Lower production costs than RIP. Maintenance-free. High reliability. Explosion-resistant. |
Medium. High production costs. Regular off-line Doble testing required. Expensive long-term storage requirements. |
Higher. Lower production costs than RIP and RIF®. Regular off-line Doble testing required. DGA testing of bushing oil recommended for older bushings. Leak mitigation. Can fail catastrophically jeopardizing the transformer, surrounding substation equipment and the safety of on-site personnel |
|
Long term storage |
No special requirements. Can be stored horizontally in their shipping crate. |
This technology uses creped insulating paper dried under temperature and impregnated under vacuum with epoxy resin. Therefore, RIP is sensitive to humidity ingress. Long term storage requires the oil end to be fitted with specially designed metallic covers filled with dry transformer oil. |
Must be stored in an upright position to avoid creating air bubbles. |
