Faraday Cup Electrometer

The Faraday cup electrometer (abbreviation: FCE ) is the simplest form of an electric meter for particulate measurement of aerosols.

Function

It consists of an electrometer and a filter called within a Faraday cage, and the Faraday cup. Charged particles, which are collected by the filter, to change the potential of the Faraday cup. Since the Faraday cup is held at a constant potential, must the trapped ions ( electrons) by electrons via a connected high-value resistor (typically 109-1011 Ω ) flow to or flow into the Faraday cup can be neutralized. Therefore, the resistance, a voltage which is a measure of the ion current ( current of electrons ), and for example an amplifier / electrometer can be measured.

Application

The Faraday cup electrometer can be used in the aerosol research for measuring the average charge of an aerosol. For this purpose, a further, independent determination of the number concentration is required. Is the state of charge of an aerosol, however, known to the FCE can be used to determine the number concentration is then directly proportional to the measured current.

• Elektrotechnisches meter
• Electrostatics
• Michael Faraday