From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The increased capacity of open-type fuses.
| Identifier | ExFiles\Box 166\7\ img092 | |
| Date | 27th January 1938 | |
| 6071. To By/from Rm{William Robotham - Chief Engineer}/RC.{R. Childs} c. to By/RD. Rm{William Robotham - Chief Engineer}/RC.{R. Childs}6/JH.27.1.38. OPEN-TYPE FUSES. The adoption of a higher-output regulator will have the effect of increasing the current that is carried by the armature fuse and to a lesser extent by the distributing fuses; by raising the working voltage of the whole system. In view of this we think that the capacity of the open type of fuse, now coming on production should be increased. This applies to both the larger one, which is to be used in place of the existing cartridge-type armature fuse, and the smaller one for standard production. The capacity of these fuses can be increased by merely retaining the gauge of wire at present used in the 30 ampere cartridge fuse, namely 28 S.W.G. tinned copper wire, instead of dropping to 30 S.W.G. wire as was intended. Bench tests show that 28 gauge of wire which fuses at about 32 amperes in its present cartridge case, has a fusing current of about 41 amperes in the smaller open type holder, and about 45 amperes in the larger special one. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||