本规范涵盖了利用金属安装表面散热原理的非建立可靠性（非ER）和建立可靠性（ER）、功率型、线绕式固定电阻器的一般要求。这些电阻器的初始电阻公差为å±1%。这些电阻器能够在+25å°C的环境温度下连续满负荷运行，并且当降额高达+250å°时（见图1）。这些电阻器不应用于交流性能对此类电路的运行至关重要的电路中。 然而，已在特定样式中作出规定，以尽量减少电感（见3.1）。这些电阻器的寿命故障率水平（FRL）范围为每1000小时1.0%至0.001%（见1.2.1.4）。这些FRL是在寿命测试的基础上以60%的置信度建立的。FRL由适当的符号标识，指的是在+25å°C的全额定功率下运行，电阻的允许变化为å±2%作为故障标准。

This specification covers the general requirements for nonestablished reliability (non-ER), and established reliability (ER), power type, wirewound, fixed resistors which utilize the principal of heat dissipation through a metal mounting surface. These resistors have initial resistance tolerances of å±1 percent. These resistors are capable for continuous full load operation at an ambient temperature of +25å¡C, and when derated up to +250å¡C (see figure 1). These resistors should not be used in circuits where their ac performance is of critical importance in the operation of such circuits. However, provisions have been made in particular styles to minimize inductances (see 3.1). These resistors will have life failure rate levels (FRL) ranging from 1.0 percent to 0.001 percent per 1,000 hours (see 1.2.1.4). These FRL are established at a 60 percent confidence on the basis of the life tests. The FRL, identified by the appropriate symbol, is referred to operation at full rated wattage at +25å¡C, with a permissible change in resistance of å±2 percent as the criteria for failure.