一、概述

     ZXD-A轉(zhuǎn)速信號(hào)測(cè)控儀可完成水輪機(jī)發(fā)電機(jī)組的轉(zhuǎn)速百分比或頻率測(cè)量，其輸入信號(hào)可取主機(jī)殘電壓（電流互感器邊）、永磁機(jī)電壓，輸出采用七路繼電器控制和一路12位D/A轉(zhuǎn)換輸出模擬量。機(jī)組的轉(zhuǎn)速百分比和頻率由四位LED數(shù)碼管顯示，七路繼電器的工作狀態(tài)由七只LED發(fā)光二極管分別指示。本儀表除可帶4—20mA ,1—5V ，0—20mA， 0—5V等標(biāo)準(zhǔn)直流信號(hào)輸出外，還可帶RS—485，RS—232C，RS—422A等標(biāo)準(zhǔn)串行口輸出，輸出采用光電隔離，使得儀表可以與計(jì)算機(jī)直接接口。

本儀表關(guān)鍵元器件采用美國(guó)ATMEL公司、 MAXIM公司、TI公司的產(chǎn)品。儀表掉電采用E²PROM數(shù)據(jù)保護(hù)，初始設(shè)置的所有參數(shù)及工作狀態(tài)不會(huì)因突然停電而丟失，可永久保存；輸入、輸出采用光電隔離技術(shù)，使得儀表完全滿足電廠安全、及時(shí)、穩(wěn)定、可靠的工作要求。

二、主要技術(shù)參數(shù)

1、輸入信號(hào)

1）發(fā)電機(jī)殘壓；2）發(fā)電機(jī)PT頻率

2、輸入電壓范圍：發(fā)電機(jī)殘壓或PT信號(hào)0.3-250VAC

3、測(cè)量精度： 0.1級(jí)

4、測(cè)頻范圍：頻率0.02 –99.99 HZ、 轉(zhuǎn)速百分比 2%-200%

5、輸出信號(hào)

1）7路繼電器常開觸點(diǎn)輸出

2）模擬信號(hào)輸出： 4—20mA (對(duì)應(yīng)于機(jī)組轉(zhuǎn)速的0%-200%)

3) RS485串行通信接口輸出：標(biāo)準(zhǔn)MODBUS通信協(xié)議

6、工作環(huán)境： 溫度-10—50 ℃ ，相對(duì)濕度≤85% 無(wú)腐蝕性氣體及導(dǎo)電、易爆、塵埃等場(chǎng)所。

7、外型尺寸 ：  寬×高×深 = 160 ×80×160 mm

8、電源 ：開關(guān)電源，交流185——250V或直流75——300V

E． Outline

 ZXDThe rotational speed signal observation meter may complete hydraulic turbine power set the rotational speed percentage or the frequency measurement, its input signal may take the main engine remnant voltage (nearby current transformer), permanent magnetism machine voltage, the output uses seven group black-white controls and a group 12 D/A transformation output simulation quantity. Unit's rotational speed percentage and the frequency demonstrated by four LED nixietubes that seven group relay's active statuses instructed separately by seven LED light emitter diode. This measuring appliance besides may bring 4-20mA, 1-5V, 0-20mA, standard cocurrent signal outputs and so on 0-5V, but may also bring RS-485, RS-232C, RS-422A and so on standard serial port output, the output uses the electro-optical isolation, causes the measuring appliance to be possible with the computer direct connection

This measuring appliance essential primary device uses American ATMEL Corporation, MAXIM Corporation, the TI Corporation's product. The measuring appliance power failure uses the E2PROM data protection, because initial establishment's all parameters and the active status will not cut power suddenly lose, but permanent preservation; The input, the output use the electro-optical isolation technology, causes the measuring appliance to satisfy the power plant safely completely, prompt, stable, the reliable work requirement

二、Major technique parameter

1、Input signal :

1）Generator remnant pressure ；2）Generator PT frequency

2、Input voltage scope ：Generator remnant pressure or PT signal 0.3-250VAC

3、Measuring accuracy:0.1 level

4、Frequency measurement scope: Frequency 0.02 - 99.99 HZ, rotational speed percentage 2%-200%

5、output signal

 1) 7 group relay normally opened contact output

2) simulated signal output: 4-20mA (corresponds to unit rotational speed 0%-200%)

3) RS485 serial communication connection output: Standard MODBUS communication protocol

6、Working conditions: Temperature - 10-50 ℃, relative humidity ≤85% non-corrosiveness gas and electric conduction, explosive, places and so on dust.

7、Outlook size: Wide * high * deep = 160 ×80×160 mm

8、Power source: The switching power supply, exchanges 185--250V or directs current 75--300V