3B Scientific 1009961 Protective Adapter, 2-Pole

Adapter for electron tubes D for connection of the heater voltage via safety experiment leads. Includes internal protective circuitry to protect the heating filament against excess voltage. Dimensions match the two-pole connector for the tubes. The use of the protective adapter, 2-pole is recommended for a number of electron tubes of the D series. The heating voltage should not be connected directly to the tubes, but with safety, the experiment leads to the adapter, which is electrically connected to the tubes. The protective adapter serves as a protective circuit for the cathode heating against overvoltage, which prevents damage to the sensitive filament of the tube. The integrated relay switches off at heating voltages of approx. 10.5 V DC and approx. 8.5 V AC and switches on again automatically after reducing the heating voltage. In-school lessons or during practical training at universities it thus counteracts incorrect operation of the heating voltage control. The protective adapter complies with the safety regulations for electrical measuring, control, and laboratory equipment according to DIN EN 61010 part 1.