24 CFR § 3280.810 - Electrical testing.
(a)Dielectric strength test. The wiring of each manufactured home shall be subjected to a 1-minute, 900 to 1079 volt dielectric strength test (with all switches closed) between live parts and the manufactured home ground, and neutral and the manufactured home ground. Alternatively, the test may be performed at 1080 to 1250 volts for 1 second. This test shall be performed after branch circuits are complete and after fixtures or appliances are installed. Fixtures or appliances which are listed shall not be required to withstand the dielectric strength test.
(b) Each manufactured home shall be subject to:
(1) A continuity test to assure that metallic parts are properly bonded;
(2) Operational test to demonstrate that all equipment, except water heaters, electric furnaces, dishwashers, clothes washers/dryers, and portable appliances, is connected and in working order; and
(3) Polarity checks to determine that connections have been properly made. Visual verification shall be an acceptable check.