They are useful in both uncontrolled and manually-switched buildings. Other features include moderate cost, convenient installation, and comprehensive service. PLC control systems will accommodate most energy management strategies not requiring fluorescent or HID dimming. PLC control systems may be highly susceptible to some forms of power line interference. PLC systems may behave erratically when used in conjunction with solid-state ballasts and other electronic devices, and they may even experience brief periods of failure due to strong interference from other systems.
Interference is also possible between systems and between zones.
Finally, dimming PLC devices are generally unsuitable for dimming of low voltage loads. In addition to the zonal lighting controls described above, some lighting controls are available that are designed to replace or augment specific luminaire components. Generally, these components can be used with any existing wiring methods. Suitable applications would include industrial and warehousing facilities. Generally, these systems are effective with any wiring methods.