柴油發(fā)電機(jī)組轉(zhuǎn)速測量保護(hù)系統(tǒng)常見故障及對(duì)策：

①傳感器與飛輪之間的距離太遠(yuǎn)或太近一般此距離約為2.5+0.3 mm。距離太遠(yuǎn)將有可能感應(yīng)不到信號(hào)，太近有可能磨壞傳感器的工作面。由于飛輪在高速運(yùn)轉(zhuǎn)中，會(huì)發(fā)生徑向（或軸向）竄動(dòng)，距離太近對(duì)傳感器的安全構(gòu)成極大威脅，曾經(jīng)發(fā)現(xiàn)有幾個(gè)探頭的工作面已被刮破。根據(jù)實(shí)際經(jīng)驗(yàn)，該距離一般在2 mm左右較為適宜，可用塞尺測量。

　　②由于傳感器安裝固定架振動(dòng)，使得測量信號(hào)不準(zhǔn)確，交變磁場產(chǎn)生不規(guī)則變化，引起轉(zhuǎn)速指示波動(dòng)。處理方法：加固該支架，可以將其與柴油機(jī)本體焊接。

　　③由于飛輪甩出來的油粘在傳感器工作面上，對(duì)測量結(jié)果產(chǎn)生一定的影響。若在飛輪上加裝防油罩，可起到良好效果。

　　④速度變送器故障，使輸出信號(hào)不穩(wěn)定，造成轉(zhuǎn)速指示波動(dòng)甚至無轉(zhuǎn)速指示，而且由于其工作不穩(wěn)定和接線頭的接觸不良會(huì)觸發(fā)電氣超速保護(hù)誤動(dòng)作。對(duì)此可用頻率發(fā)生器輸入頻率信號(hào)對(duì)速度變送器進(jìn)行校驗(yàn)，端子進(jìn)行緊固。由于該速度變送器為PLC微電腦控制，必要時(shí)可重新調(diào)整或更換。

　　⑤傳感器故障。　在測量好間距之后，開盤車機(jī)觀察傳感器上的紅色發(fā)光二極管，當(dāng)飛輪齒通過時(shí)，其發(fā)光亮度會(huì)明顯增強(qiáng)，或不開盤車機(jī)用金屬物靠近或遠(yuǎn)離傳感器，觀察紅色發(fā)光二極管亮度有無變化，如果亮度沒有變化或者根本沒有發(fā)光，則可能是傳感器損壞，需要更換。CMR524系統(tǒng)在起動(dòng)時(shí)報(bào)“調(diào)速器故障”，大都是傳感器故障。

Common faults and countermeasures of speed measurement and protection system for diesel generator set:

① The distance between the sensor and the flywheel is either too far or too close, typically around 2.5+0.3 mm. If the distance is too far, it may not sense the signal, and if it is too close, it may damage the working surface of the sensor. Due to the radial (or axial) movement of the flywheel during high-speed operation, the proximity poses a great threat to the safety of the sensor. It has been found that the working surfaces of several probes have been scratched. Based on practical experience, a distance of around 2 mm is generally suitable and can be measured with a feeler gauge.

② Due to the vibration of the sensor mounting bracket, the measurement signal is inaccurate, and the alternating magnetic field produces irregular changes, causing fluctuations in the speed indication. Solution: Strengthen the bracket by welding it to the diesel engine body.

③ Due to the oil thrown out by the flywheel sticking to the working surface of the sensor, it has a certain impact on the measurement results. If an oil guard is installed on the flywheel, it can have a good effect.

④ The malfunction of the speed transmitter causes unstable output signals, resulting in fluctuations or even no speed indication. Moreover, due to its unstable operation and poor contact of the wiring head, it can trigger electrical overspeed protection misoperation. To verify the speed transmitter, a frequency generator can be used to input a frequency signal, and the terminals can be tightened. Due to the speed transmitter being controlled by a PLC microcomputer, it can be readjusted or replaced if necessary.

⑤ Sensor malfunction. After measuring the spacing, open the car machine and observe the red LED on the sensor. When the flywheel teeth pass through, its brightness will significantly increase. Alternatively, if the car machine is not opened and a metal object is used to approach or move away from the sensor, observe whether the brightness of the red LED has changed. If there is no change in brightness or no light at all, it may be that the sensor is damaged and needs to be replaced. The CMR524 system reports a "governor fault" during startup, mostly due to sensor malfunctions.