IS200AVGCG1A通用电气卡件,工控卡件
还必须输入电机满载振幅（FLA）值。该值可取自电机铭牌数据表。服务系数可作为过载传感器输入（见第4–26页第4.6节：S5热模型）。对于高电阻接地系统，如果使用50:0.025接地CT输入，则可以进行灵敏的接地电流检测。要使用50:0.025输入，请为地面CT设置点选择“Multiline 50:0.025”。不会出现其他地面CT信息。在故障电流可能相当大的可靠接地系统上，469 1A或5A次级接地CT输入应用于零序或剩余接地传感。如果连接是剩余的，则接地CT次级和初级值应与相位CT相同。但是，如果连接是零序，则必须输入接地CT二级和初级值。应选择接地CT一次，使潜在故障电流不超过一次额定值的20倍。当购买继电器级CT时，该预防措施将确保接地CT在故障条件下不会饱和。如果要使用差动特性，必须输入相位差动CT主设定点。如果在矢量求和配置中每相使用两个CT，则应选择CT以确保电机启动期间没有饱和。然而，如果每相的差动保护使用铁芯平衡CT，则50或100 a的低CT额定值允许非常灵敏的差动保护。使用双速电机功能时，必须在此处为速度2输入第二组相位CT和电机FLA的值。如果相位CT与速度1相位CT相同，只需在此处输入相同的值即可。如果要进行计算，则必须输入电压互感器的匝数比。电压互感器比率的选择必须确保当一次电压为电机铭牌电压时，VT的二次电压介于40和240 V之间。所有需要电平设置点的电压保护特性均编程为电机铭牌电压或额定电压的百分比，其中，电机铭牌电压表示额定设计信息逃生信息逃生信息GE电源管理469电机管理继电器4-13 4设定点编程4.3 S2系统设置4 4.3.3电源系统在此处输入标称系统频率。这些设定值允许469确定内部采样率以获得最大精度。当标称系统频率设置为“可变”时，469可用于变频驱动器。所有元件都以相同的方式工作，但以下情况除外：负序电流与正序电流的比率计算范围为0至30%，而不是40%，如果电压波形近似正弦，电压和功率元件将正常工作。来自脉宽调制驱动器的未滤波电压波形不能被精确测量；然而，电流波形是近似正弦的并且可以精确地测量。所有电流元件将正常工作。然而，请注意，使用可变频率时，欠压和欠频元件不会立即工作。如果选择“变量”，当液位接近阈值时，过滤算法会将跳闸和报警时间增加270 ms。如果液位大大超过阈值，跳闸和报警时间将减少，直到与编程延迟相匹配。
A value for MOTOR FULL LOAD AMPS (FLA) must also be entered. The value may be taken from the motor nameplate data sheets. The Service Factor may be entered as Overload Pickup (see Section 4.6: S5 THERMAL MODEL on page 4–26). For high resistance grounded systems, sensitive ground current detection is possible if the 50:0.025 ground CT input is used. To use the 50:0.025 input, select "Multilin 50:0.025" for the GROUND CT setpoint. No additional ground CT messages will appear. On solidly grounded systems where fault currents may be quite large, the 469 1A or 5A secondary ground CT input should be used for either zero-sequence or residual ground sensing. If the connection is residual, the Ground CT secondary and primary values should be the same as the phase CT. If however, the connection is zero-sequence, the Ground CT secondary and primary values must be entered. The Ground CT primary should be selected such that potential fault current does not exceed 20 times the primary rating. When relaying class CTs are purchased, this precaution will ensure that the Ground CT does not saturate under fault conditions. The PHASE DIFFERENTIAL CT PRIMARY setpoint must be entered if the differential feature is to be used. If two CTs are used per phase in a vectorial summation configuration, the CTs should be chosen to ensure there is no saturation during motor starting. If however, a core balance CT is used for the differential protection in each phase, a low CT rating of 50 or 100 A allows for very sensitive differential protection. When the two-speed motor feature is used, a value for a second set of Phase CTs and motor FLA must be entered here for Speed 2. If the Phase CTs are the same as the speed 1 phase CTs, simply enter the same value here as well are to be made, the turns ratio of the voltage transformers must be entered. The VOLTAGE TRANSFORMER RATIO must be chosen such that the secondary voltage of the VTs is between 40 and 240 V when the primary is at MOTOR NAMEPLATE VOLTAGE. All voltage protection features that require a level setpoint are programmed as a percent of the MOTOR NAMEPLATE VOLTAGE or rated voltage, where MOTOR NAMEPLATE VOLTAGE represents the rated design MESSAGE ESCAPE MESSAGE ESCAPE MESSAGE ESCAPE GE Power Management 469 Motor Management Relay 4-13 4 SETPOINT PROGRAMMING 4.3 S2 SYSTEM SETUP 4 4.3.3 POWER SYSTEM Enter the nominal system frequency here. These setpoints allow the 469 to determine the internal sampling rate for maximum accuracy. The 469 may be used on variable frequency drives when the NOMINAL SYSTEM FREQUENCY is set to "Variable". All of the elements function in the same manner with the following exceptions: the ratio of negative to positive sequence current is calculated from 0 to 30%, not 40%, and the voltage and power elements will work properly if the voltage waveform is approximately sinusoidal. An unfiltered voltage waveform from a pulse width modulated drive cannot be measured accurately; however, the current waveform is approximately sinusoidal and can be measured accurately. All current elements will function properly. Note, however, that undervoltage and underfrequency elements will not work instantaneously using variable frequency. If "Variable" is chosen, the filtering algorithm increases the trip and alarm times by up to 270 ms when the level is close to the threshold. If the level exceeds the threshold by a significant amount, trip and alarm times will decrease until they match the programmed delay.
