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).
Technical note on suppressing engine electrical interference by bonding the engine and metalwork to the chassis.
| Identifier | ExFiles\Box 168b\1\ img270 | |
| Date | 6th May 1938 guessed | |
| Suppression of engine interference. Electrical interference radiated by the engine is due mainly to the following equipment 1. Ignition 2. Dynamo & regulator 3. Brake & Wheel Static 4. Windscreen wipers. Petrol pump. car heater. To give the theory & reason for this type of interference is outside the scope of these notes, they deal only with its elimination. The following methods of suppressing this equipment have been used on Rolls-Royce & Bentley cars. Before proceeding to outline the various methods adopted it is essential that the engine & associated metal work is thoroughly bonded to the chassis, the importance of this cannot be overemphasised. The bonding strips consist of heavy flexible braided copper about 1" in width & 1/8 in depth. Their length will vary according to where they are fitted, however they must be kept as short as possible. The recommended positions are as follows, from the top of the gear box onto the bottom of the dashboard, & should be fitted so that it has a certain percentage of flexibility. The next bond is connected from the lower half of the gear box onto the main frame of the chassis again leaving some slack, this is to counteract for vibration. After the length of these conductors have been decided it is necessary to sweat together the ends of braiding about 1 1/2" of each end, then drill a 5/16" hole through the centre of the braiding 3/4" from each end. | ||