These requirements cover energy management equipment and associated sensing devices rated 600 volts or less and intended for installation in accordance with the National Electrical Code@ NFPA 70. This equipment energizes or de-energizes electrical loads to achieve a desired use of electrical power. The equipment is intended to control electrical loads by responding to sensors or transducers monitoring power consumption@ by sequencing@ by cycling the loads through the use of preprogrammed data logic circuits@ or any combination thereof. Devices responding to signals from a utility company may receive the signals over the power lines or as radio signals. These requirements also cover equipment intended for connection only to a low-voltage circuit of limited power supplied by a Class 2 transformer. These requirements do not cover switching devices operated by a mechanical or electromechanical clock mechanism to energize or de-energize loads. These requirements do cover electronic clock operated energy management equipment. Controls intended to be installed in air handling spaces or in other environmental air space (plenums) are covered under the scope of this standard.