1. Overview
ZKZ-3T speed monitoring device is connected with external speed pulse sensor and voltage transformer signal to monitor the speed of the hydro-generator set in real time, and output the switch signal and the analog signal corresponding to the speed of the unit at each speed point of the unit. Shutdown and power plant monitoring system services.
2. Features
1. ZKZ-3T rotational speed monitoring device integrates frequency meter, tachometer, rotational speed relay and rotational speed test instrument. It is a multi-purpose rotational speed monitoring instrument.
2. The speed monitoring device has communication function, and the software has built-in standard MODBUS communication protocol.
3. The rotational speed measurement adopts a high-performance microprocessor CPU as the core measurement device, which has the characteristics of high measurement accuracy and strong real-time performance.
4. The measurement and control accuracy of the device only depends on the error and stability of the crystal oscillator, so the output value of the speed contact can maintain long-term operation without change.
5. The speed contact output adopts the hysteresis blocking method to prevent the output malfunction caused by waveform distortion. According to the operation needs of the power plant, the 8 speed output values can be easily adjusted in a certain range on site.
6. The device also has a standard 4-20mA current output, which can be easily interfaced with a computer, and can be used as an integral part of the computer monitoring system of the entire hydropower plant.
3. Technical performance
Number of measurement signal channels: one pulse signal, one PT signal (or permanent magnet machine signal)
Measurement frequency range: 0.5～100Hz
Measurement accuracy: Non-linearity <1%, speed dead zone <0﹒02%
Digital display content: Generator frequency, speed percentage, output setting value of each channel.
Switch value output signal: Speed value signal: 8 channels, each point can be set by the user within the specified range.
Creep monitoring signal: 1 channel, the contact is closed when the speed is 0.05%~1%Ne
Device power failure alarm signal: 1 channel, the contact is closed when abnormal
Analog output: 4～20mA (corresponding to the unit speed 0%Ne～200%Ne)
Output contact capacity: 0.3A/220VDC, 1A/30VDC
Dimensions: 160 x 80 x 250mm on a plate
Power supply: DC120～340V or AC85～265V/50Hz
4. Panel description
1. The fm light is on: the displayed value is the frequency measured by the PT input signal; the fp light is on: the signal frequency of the toothed disc is displayed; the n% light is on: the displayed value is the speed percentage.
2. J1-J8 relay alarm output indicator light.
3. Peristalsis monitoring signal RD: the contact is closed for 4 minutes when the speed is 0.05% to 1% Ne
5. Terminals
Power supply: Terminals 1 and 2, regardless of positive and negative poles.
PT signal: Terminals 3 and 4.
Gear plate signal: 5 (V is connected to the pulse sensor power supply +24V), 6 (F is connected to the pulse sensor signal input terminal), 7 (C is connected to the pulse sensor signal ground).
4-20mA output: 8 (current positive), 9 (current negative).
Communication: 10(A), 11(B).
Ground: 12 (Case Ground)
Relay outputs: 13 to 32
J9 contact: the contact is closed when the device power failure alarm or power failure;
J10 contact: peristalsis monitoring contact, the contact is closed after monitoring the peristalsis.
6. Installation size
The appearance of the instrument and the size of the opening are shown in the following figure:
