Industrial Weston Reference Cell D-845-D

The Reference Cells are characterised by a negligible temperature coefficient, ensuring a constant EMF over a wide range of temperatures, and a negligible hysteresis effect, enabling the cell to rapidly reach stability after a change of temperature.

Connexions are made to the cell electrodes by means of flexible PVC-covered wires soldered to the platinum lead-out wires, the PVC sleeving being coloured red and black to denote polarity. The base of the cell limbs, including the soldered junctions, are plastic-coated to secure the leads against vibration.

The final test is made at 25°C for both EMF and internal resistance; the positive limb is then labeled with the serial number and the date of the test. According to customer requirements, each cell is provided with a certificate of test or tie-on tag giving the actual voltage on the final test at 25°C to an accuracy of 0·01 %.

D-345 REFERENCE CELL

Several versions of this cell are available, the complete range covering a variety of applications.

The basic cell, which is an unmounted type, is the D-845-C; external connexions are made by means of 9-inch flexible leads.

Two standard-mounted versions are available: the D-845-A and the D-845-D.

SPECIFICATION

The guaranteed accuracy of EMF on the Test Certificate is 0·01 % for all models; the temperature coefficient is less than ±5 µV over the range 10 °C  to 40 °C.

In questo link sono elencati 28 modelli, di cui 22 con immagini e 1 con schemi.
Elenco delle radio e altri apparecchi della Muirhead & Co. Ltd.; Beckenham