Accession No

3660

Brief Description

moving iron, pointer ammeter, by Hartmann & Braun, German, 1900

Origin

Germany; Frankfurt

Maker

Hartmann & Braun

Class

electrical

Earliest Date

1900

Latest Date

1900

Inscription Date

Material

wood; metal (brass, iron); paper

Dimensions

height 230mm; base diameter 108mm

Special Collection

Cavendish collection

Provenance

Transferred from Cavendish Laboratory, University of Cambridge, Cambridge, England. Listed in the Cavendish Numerical Catalogue: ‘bought 1900’.

Inscription

‘HARTMANN & BRAUN
FRANKFURTa/M.
18960
R.PATENT’ (on base)
‘AMP. (with AC symbol)’ (on vertical dial)
‘E.540A’ (on base (added))

Description Notes

Circular wooden base; two brass terminals; vertical solenoid on wooden former; vertical brass tube above solenoid houses moving iron and attached pointer, suspended by a spring; moving iron is tubular, concentric with outer tube, with two tear-drop shaped holes cut in its side; white paper dial on outside of tube; two scales: 0 to 6 cm, and non-linear 0 to 10 amperes; brass zero adjustment at top of tube.

Condition: good; complete.

References

Events