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).
Whether to fit an ammeter to a chassis with a vibrator-controlled dynamo.
| Identifier | ExFiles\Box 168\5\ img246 | |
| Date | 29th March 1933 | |
| To R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Wst. A.{Mr Adams} L. H.{Arthur M. Hanbury - Head Complaints} C. Wor.{Arthur Wormald - General Works Manager} PH. C. Ry. DA.{Bernard Day - Chassis Design} x6132 Hs{Lord Ernest Hives - Chair}/Wst.3/KT. 29.3.33. DELETION OF AMMETER ON CHASSIS. In connection with the fitting of vibrator controlled dynamos to our chassis, the question of whether or not we should fit an ammeter, should be considered. The ammeter is really not necessary with the compensated voltage system, and it would be misleading unless it is observed by someone who is cognisant of the principle of the set. Where an ammeter is fitted the driver may notice a very small charge reading and assume that the dynamo has developed a fault. Thus although the battery may be fully charged and the dynamo perfectly all right, he will assume that something is wrong and spend a lot of time looking for the trouble, and possibly tamper with the regulator. Messrs. Bosch have for years dispensed with an ammeter and rely solely on the red lamp indicating charge or no charge. Another difficulty experienced with the ammeter on chassis where a vibrator is fitted, is the oscillation of the ammeter needle. With the existing standard Lucas instrument the instrument is unreadable with the regulator in action and a moving coil ammeter or a modified moving iron ammeter having suitable damping has to be used. On the other hand the ammeter is a useful instrument for checking the discharges of accessories etc. and we would be glad if all concerned would let us have their views on the matter. Hs{Lord Ernest Hives - Chair}/Wst. | ||