IS200BPVCG1BR1工控模块机器人备件
欠电流/欠功率38轴承RTD 46电流不平衡47相位反转49定子RTD 50短路备份50G/51G接地过电流备份51过载55功率因数66启动/小时和启动间隔时间81频率86过载锁定87差动469电机保护系统GEGridSolutions.com 3不平衡（负序电流）偏置负序电流，在电机制造商提供的热极限曲线中没有考虑到引起转子发热的温度。469将不平衡量测量为负序电流与正序电流之比。热模型被偏置以反映额外的加热。由于电流不平衡导致的电机降额可通过设置点不平衡偏置k因子进行选择。不平衡电压导致的电流不平衡水平大约高出6倍（电压不平衡的1%等于电流不平衡的6%）。注意，k=8曲线几乎与NEMA降额曲线相同。热/冷安全失速比热/冷安全失速时间比定义了电机使用的热容量（TCU）的稳态水平。该水平对应于满载电机的正常工作温度，如果电机负载低于额定值，则将按比例调整。继电器使用热/冷安全失速比来确定运行冷却曲线的下限，并定义RTD偏置曲线中中心点的热容量水平。电机冷却时间常数当469检测到电机以低于过载拾取设定值的负载运行，或电机停止时，它将开始降低存储的TCU值，模拟实际电机冷却过程。TCU以冷却时间常数设定值规定的速率呈指数衰减。通常，停止的电机的冷却过程比运行的电机慢得多，因此在继电器中提供了运行和停止冷却时间常数设定值，以反映差异。运行冷却曲线的TCU下限由热/冷安全失速比和电机负载水平定义。停止冷却曲线的TCU下限为0%，对应于环境温度下的电机。启动抑制和紧急重启当热容量不足或电机启动监控功能指示启动抑制时，启动抑制功能可防止电机启动。在紧急情况下，可重置所用热容量和电机启动监控计时器，以允许热电机启动。RTD偏置469热过载曲线仅基于测量电流，假设环境温度为40°C，电机冷却正常。由于环境温度异常高或电机冷却堵塞，实际电机温度将升高。如果电机定子具有嵌入式RTD，则使用RTD偏置功能来增加热容量的热模型计算。RTD偏置特性是测量定子温度的反馈。Undercurrent/Underpower 38 Bearing RTD 46 Current Unbalance 47 Phase Reversal 49 Stator RTD 50 Short circuit backup 50G/51G Ground overcurrent backup 51 Overload 55 Power factor 66 Starts/hour and time between starts 81 Frequency 86 Overload lockout 87 Differential 469 Motor Protection System GEGridSolutions.com 3 Unbalance (Negative Sequence Current) Biasing Negative sequence current, which causes rotor heating, is not accounted for in the thermal limit curves supplied by the motor manufacturer. The 469 measures unbalance as the ratio of negative to positive sequence current. The thermal model is biased to reflect the additional heating. Motor derating due to current unbalance can be selected via the setpoint unbalance bias k factor. Unbalance voltage causes approximately 6 times higher level of current unbalance (1% of voltage unbalance equal to 6% of current unbalance). Note that the k=8 curve is almost identical to the NEMA derating curve. Hot/Cold Safe Stall Ratio The Hot/Cold Safe Stall time ratio defines the steady state level of thermal capacity used (TCU) by the motor. This level corresponds to normal operatingtemperature of the fully loaded motor and will be adjusted proportionally if motor load is lower then rated. The Hot/Cold Safe Stall ratio is used by the relay to determine the lower limit of the running cool down curve, and also defines the thermal capacity level of the central point in RTD Biasing curve. Motor Cooling Time Constants When the 469 detects that the motor is running at a load lower then overload pickup setpoint, or the motor is stopped, it will start reducing the stored TCU value, simulating actual motor cool down process. TCU decays exponentially at a rate dictated by Cooling Time Constants setpoints. Normally the cooling down process of the stopped motor is much slower than that of a running motor, thus running and stopped cooling time constants setpoints are provided in the relay to reflect the difference. The TCU lower limit of the running cool down curve is defined by Hot/Cold Safe Stall Ratio and level of the motor load. The TCU lower limit of the stopped cool down curve is 0% and corresponds to motor at ambient temperature. Start Inhibit and Emergency Restart The Start Inhibit function prevents starting of a motor when insufficient thermal capacity is available or motor start supervision function dictate the start inhibit. In case of emergency the thermal capacity used and motor start supervision timers can be reset to allow the hot motor starting. RTD Biasing The 469 thermal overload curves are based solely on measured current , assuming a normal 40°C ambient and normal motor cooling. The actual motor temperature will increase due to unusually high ambient temperature, or motor cooling blockage. Use the RTD bias feature to augment the thermal model calculation of Thermal Capacity Used, if the motor stator has embedded RTDs. The RTD bias feature is feedback of measured stator temperature.
