The high-voltage spark ignition of gas burners and directly lit or gas-ignited oil burners is the purpose of the ignition transformers TZI and TGI. Single-electrode burners, in which the ionization and ignition currents pass through a shared electrode, can also be operated using ignition transformers. The IP 20 enclosure criteria are met by the ignition transformer TZI. Installation in a control cabinet is appropriate for it. The die-cast aluminum casing of the ignition transformer TGI satisfies IP 65 enclosure standards. Installing it close to the burner on-site is OK.