Abstract: An automatic pig-charging apparatus for hot-chamber pressure-diecasting machines is described, which enable small parts to be manufactured e.g., a Zamak alloy especially under mass production conditions. Excessive fluctuations of the level of the liquid metal melt have prove to have disadvantageous effects on the quality of small parts, and on the service lives of the pressure-diecasting machines and dies. The aim must accordingly be to minimize the fluctuations. The present invention provides a control system, which keeps the liquid metal level within narrow limits. A float switch automatically triggers a charging operation whenever the lower liquid metal level is reached. This operation involves the automatic replenishment of the liquid metal melt by addition of pigs supplied from a replenishing station.