Meter No. 20A and 20B
Resettable meter that would be fitted to a P.M.B.X. when metering was required.

These were produced by the Stonebridge Electrical Company.

These could be fitted in a wooden Case No. 24, which was fixed to the switchboard.

Superseded by the Meter No. 21.

Meter No. 20A - 20-30volts DC.
Meter No. 20B - 45-55volts DC.

Required a Unit, Metering No. 1 to operate.

Click here for metering schemes and apparatus required - Telephones, PBX B3104

 

 
 
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Last revised: September 24, 2025

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