[国外标准] NEMA DC 5-1989(R2008) Residential Controls – Surface-Type Controls for Electric Storage Water Heater
[国外标准] NEMA DC 3-2008 Residential Controls–Electrical Wall-Mounted Room Thermostats
[国外标准] NEMA DC 10-2009 Residential Controls—Temperature Limit Controls for Electrical Baseboard Heaters