Any number and any type of Class 1 circuit conductors may be installed in the same conduit, raceway, box, or other enclosure if all conductors are insulated for the maximum voltage at which any of the conductors operates and the wires are functionally associated with each other.
Class 1 circuit wires may be run in raceways by themselves according to the NEC ®. The number of conductors in a conduit must be determined from tables 1 through 5 in chapter 9 of the NEC ® ).
In figures 7-11 and 7-12, you see the electrical symbols that conform to the standards established by the National Electrical Manufacturer's Association (NEMA). Where NEMA standards do not exist, American Standards Association (ASA) standards are used; however, not all manufacturers use these established symbols. In spite of the lack of standardization, knowledge of the symbols presented in this unit will give you a firm basis for interpreting variations found in the field.
Figure 7-11. - Standard wiring diagram symbols.Continue Reading