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).
Specification table for a Weston Box Instrument Model 163 with its electrical characteristics and connection diagrams.
| Identifier | ExFiles\Box 165\3\ img030 | |
| Date | 31th December 1920 guessed | |
| -7- | Description | Number and connection | Volt ranges | Ampere ranges | Resistances (Ω) | Remarks | | :--- | :--- | :--- | :--- | :--- | :--- | | | 98. | .0168 (at 15°C.) | .0105 | 1.600 (at 15°C) | Instrument only. | | Weston Box Instrument Model 163 | 1.5 | .0497 (at 18°C.) | .0188 | 2.64 (at 18°C) | Between external shunt terminals. | | | (Connection Diagram) | 1.5 | X | 142.9 | Internal volt coil box. | | | Instr A V + - 15 150 | 15 | X | 1429 | | | | | 150 | X | 14290 | | | | | X | 1.5 | .0333 | External shunts. | | | | X | 15 | .00331 | | | ||