Category:AD16 (AD22) series lamps

English: The AD16 and the less common, and interchangeable, AD22 is the standardized form-factor of panel lamps for through-hole installation. The two digits that follow the AD16 or AD22 code denote the mounting hole diameter, for example the common AD16-22 requires a 22 millimeter round hole. The AD16-22 is large enough to house a single electronic voltmeter or ammeter (with an external current transformer or shunt), or a compound meter with V, A and Hz readout all in one "lamp"). According to Siemens datasheets, the nomenclature of AD16 lamps is governed by the Shanghai Electrical Apparatus Research Institute.