Ndi electro-mechanical m'chilengedwe.Chofunikira apa ndikuti:
1.Itha kulumikizidwa mbali iliyonse.
2. Imagwirizana ndi IEC/EN 61008-1 (main voltage odziyimira pawokha RCCB), Ili ndi kutulutsa kwamagetsi komwe kumagwira ntchito mosatekeseka ngakhale popanda voteji kapena voteji yotsika kuposa 50V.
3.Type -A: Imateteza ku mitundu yapadera ya DC yotsalira pulsating yomwe siinasinthidwe.
4.Kutetezedwa kwa anthu motsutsana ndi kugwedezeka kwa magetsi mwa kukhudzana mwachindunji (30 mA).
5.Kutetezedwa kwa anthu motsutsana ndi kugwedezeka kwa magetsi ndi kukhudzana kwachindunji (300 mA).
6.Kutetezedwa kwa makhazikitsidwe ku zoopsa zamoto (300 mA).
7. Amapereka chitetezo chokwanira ku machitidwe ogawa nyumba ndi malonda.