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 testing of a dynamo field fuse for a Bensport wiring diagram.
| Identifier | ExFiles\Box 168\1\ img126 | |
| Date | 29th May 1933 | |
| 86117 E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to By/RD. Hs{Lord Ernest Hives - Chair}/Wst.2/MA.29.5.33. BENSPORT WIRING DIAGRAM. In response to your request for us to carry out a test with the dynamo field fuse protecting both the cutout shunt coil and the dynamo field, we have now completed the test and we give below our results. It was found that with the dynamo running on open circuit and the cutout shunt coil across its terminals, it was possible to reach a voltage of 62 across the shunt coil before the field fuse blew. The standard field fuse is arranged to blow at about 6.3 to 6.8 amperes. With the voltage of 62 the current was 5.9 amperes and after 40 mins., running the cutout shunt coil was found to be badly scorched. This definitely confirms our original contention that the dynamo armature fuse should be between the regulator and the cutout and not between the switch and cutout. The above remarks of course refer to the condition where the regulator sticks on contact. Hs{Lord Ernest Hives - Chair}/Wst. | ||