ZKZ-3/T type speed monitoring device is connected with the speed pulse sensor, signal of voltage transformer, the speed of real-time monitoring of hydrogenerator and in the unit the speed output switch quantity signal and corresponds to the rotational speed of the unit, analog signal, automatic start and stop and power plant monitoring system service.
Two, features
Exergy ZKZ-3/T type speed monitoring device set frequency meter, tachometer, speed relay, speed testing instrument in one, is a multipurpose speed monitoring instrument;
- speed measurement using the principle of advanced measurement gate door cycle, has the characteristics of high measuring precision, strong real-time;
Device control precision depends only on the error and stability of the crystal, so speed contact export value can maintain long-term operation and does not change;
- speed contact output used to difference the locking prevents the waveform distortion caused by the misoperation of the output, according to the needs of the plant operation can be at the scene easily speed are exported to eight values for a range of tuning.
- the device has a standard 4 ~ 20mA current output, optional RS485 (MODBOS RTU), communication output can facilitate the connections and computer monitoring system of the whole plant.
Three, the main technical performance
A number of measurement signals: pulse signal, a PT signal (or magnetic signal)
Measurement frequency range: 0.05 ~ 100Hz
The measurement accuracy: the nonlinear degree is 1%, the speed of the dead zone is 0. 2%
Digital content: generator frequency, speed of rotation, the output of the whole set value.
The output signal of the switch output signal: the speed value signal: 8 way, each point can be determined by the user within the range specified.
1 way (SPST) of the output signal of the alarm output signal of the unit
Device power failure alarm signal 1 way
Analog output: 4 ~ 20mA (corresponding to the unit speed 0%Ne ~ 200%Ne)
Communication output: RS485 (RTU MODBOS)
Working environment: temperature 50 ~ 0 humidity < 85%
Dimensions: 160 x 80 x 250mm
Working mode: continuous
Power supply: DC110 ~ 340V or AC85 ~ 265V/50Hz
Power consumption: 12W
四、工作原理
ZKZ-3/T型轉(zhuǎn)速監(jiān)控裝置由齒盤、傳感器及監(jiān)測裝置本體三部分構(gòu)成。監(jiān)測裝置采用了MCS-51系列單片機系統(tǒng)。系統(tǒng)內(nèi)部分頻后產(chǎn)生測量定時脈沖，周期為2us,其測量精度可達0.01HZ,穩(wěn)定性高，長期不變。顯示電路采用高亮度動態(tài)顯示方案，亮度高。
信號測量電路有隔離、放大、整形功能，兩路信號完全獨立，當齒盤信號斷線時，自動切入PT信號，0.3V~250V范圍內(nèi)的信號電壓能長期可靠工作，300V以內(nèi)也能斷短期可靠工作。測速齒盤將其方波信號取入計算機內(nèi)，再換算對應(yīng)的頻率、轉(zhuǎn)速、轉(zhuǎn)速百分比等內(nèi)容提供顯示、記憶。ZKZ-3/T測速裝置具有機組蠕動報警功能，當機組停機發(fā)生蠕動時，便發(fā)出蠕動報警信號。