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- Archive
- PRESS RELEASE: James Fisher and Sons plc announces new Head of Defence
- NEWS: JFD secures two nominations at the 2023 Subsea Expo Awards
- PRESS RELEASE: JFD supports highly successful NATO submarine rescue system aircraft loading exercise with the US Air Force
- PRESS RELEASE: JFD wins £63M ‘Third In-Service Support’ NATO submarine rescue system contract
- Archive
- Divulged - Winter 2017
- Divulged - Summer 2017
- Divulged - Winter 2016
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- Divulged - Winter 2019
- Divulged 2021 Edition 1
- UDT 2019
- Visit JFD at UI 2016
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- JFD LEXMAR is exhibiting at OSEA 2016
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- Explore our commercial capabilities at Bergen International Diving Seminar
- JFD showcasing commercial and defence capabilities at Underwater Intervention
- JFD exhibiting alongside James Fisher Offshore at Subsea Expo
- Visit our stand at DSEI 2021!
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- Visit JFD Australia at Indo Pacific 2022
- JFD North America is exhibiting at SOFIC 2022
- Experience CNE 2022 with JFD
- Discover JFD at UDT 2022
- Join JFD at GSOF Symposium Europe this October
Ultrathermics circuit breaker
Highly acclaimed, the robust Ultrathermics circuit breaker is now fitted to most diving control systems around the world.
The totally enclosed design offers full protection to the surface operator from unintentional contact whilst also shielding them from the visual arc spark during the breaking of the circuit. The single switching action breaks both poles of supply thereby rendering the cutting / welding equipment safe.
The Ultrathermics circuit breaker is a two pole, 630 amp AC or DC circuit breaker for direct surface control of underwater cutting and welding operations.
| Item | Order Code |
| Ultrathermics 630 circuit breaker 630 AMP | UL148 |
| Ultrathermics 400 circuit breaker 400 AMP | UL149 |
| Ultrathermics 250 circuit breaker 250 AMP | UL150 |
| Type | Document | Download |
| Datasheet | Ultrathermics circuit breaker | |
| Drawing | Circuit breaker 630A | UL148S1 R0 |
| Drawing | Circuit breaker 400A | UL149S1 R0 |
| Item | Order Code |
| Ultrathermics 630 circuit breaker 630 AMP | UL148 |
| Ultrathermics 400 circuit breaker 400 AMP | UL149 |
| Ultrathermics 250 circuit breaker 250 AMP | UL150 |
| Type | Document | Download |
| Datasheet | Ultrathermics circuit breaker | |
| Drawing | Circuit breaker 630A | UL148S1 R0 |
| Drawing | Circuit breaker 400A | UL149S1 R0 |
