请问可能按照附图用PIC 10位ADC进行三相电压测量吗？

不。



      以下为原文

    No.

你能告诉我原因和其他选择吗？或者我需要在所附的框图中进行更改。我引用了以下链接：HTTP://EngEngRealEngs/COM/3相电压。



      以下为原文

    Thanks robertvwhite,
 
Can you specify me the reason and any alternative ? 
 
Or What I need to change in the attached block Diagram .
 
I have taken reference from  Link as below:
 
http://engineerexperiences.com/3-phase-voltage.html
 
 
Thanks again
 
*TS9* 
 

确保所有引脚上的电压都保持在gnd和Vcc之间。关于A/D测量和使用输入箝位二极管引起的泄漏电流，有一个很好的应用说明。如果有一个稍微超过Vcc的输入，箝位电流可以使另一个AtoD输入采取更多的电流t。汉族正常和测量将是错误的。



      以下为原文

    Make sure that all the voltages at the pic pins remain between gnd and Vcc.
There is a good application note about A/D measurements and leakage currents caused by using the input clamping diodes.
 
If there is an input slightly over Vcc, the clamp current can make another AtoD input take more current than normal and the measurement will be wrong.
 
 

嗨，DougRice，谢谢你的更新，这意味着在MSG 1中的框图中是可能的。实际上我已经给直接交流步降0到3.3V，然后读峰值。请写给我那个链接，我也会处理。你能让我知道。这个拓扑的主要优点和缺点是什么？超专用集成电路TS9*



      以下为原文

     
Hi DougRice,
 
Thanks for your Update 

That means it is possible at in Block Diagram in Msg #1. ?
Actually I have fed direct AC Stepped Down 0 to 3.3V and then Reading Peak value.
 

Please write me link of that also.
 

 
I will take care of that .
 
Can you let me know .
What are the main merits and demerits of this topology ? over dedicated IC
 
*TS9*
 
 
 

请更新我。



      以下为原文

    Please Update me.

请在等待主题前24小时。



      以下为原文

    Please wait 24 hours before bumping a topic.
 

一个问题是你的图表过于简单化。你想感应线到线还是线到中性？这不清楚，你的图表显示了我作为底盘接地的符号。你的“地面”符号真的只是指示一个共同的信号返回吗？或者你是指连接到保护地球的连接？如果你有一个四线的星形连接系统，那么“地”符号是否意味着“中性”？电阻分压器电路是模糊的，因为您只显示两个连接，但必须至少有三个。第三个连接在哪里？在使用电源电压时，安全是至关重要的。由于您使用的字母是R、Y和B，所以我认为您在美国之外，可能使用416./230./50Hz系统。你知道你的电路需要多少爬电和净空距离吗？LCD是否提供足够的绝缘、爬行和间隙来保护可能接触到LCD表面的用户？您的辅助电源显示为连接线到线，但参照您的“地”。我不知道这是如何工作的。也许你提供了你所设想的电路的完整示意图，并且能够给你提供更好的反馈。还有一件事，在你提供的链接中，请注意，在图2中，所感测到的交流电压显然是来自三相阶梯道输出的低电压。N型变压器你的电路里有这样的变压器吗？还要注意，所感测的是线路的峰值电压，并且电路没有直接测量交流电压。



      以下为原文

    One problem is that your diagram is too simplistic.  Are you trying to sense line-to-line or line-to-neutral?  This is not clear.
 
Your diagram shows the symbol for ground which I take as a chassis ground.  Is your "ground" symbol really only to indicate a common signal return?  Or are you meaning a connection to the protective earth connection?  If you have a four-wire wye connected system, does the "ground" symbol mean the "neutral"?
 
The resistive divider circuit is ambiguous as you only show two connections but there must be at least three.  Where is the third connection?
 
Safety is paramount when working with mains voltages.  Since you use the letters R, Y, and B I take it that you are outside the US and probably working with a 416 Vac/230 Vac/50 Hz system.  Do you know what the required creepage and clearance distances are for your circuit?  Does the LCD provide adequate insulation, creepage, and clearance to protect a user that might touch the face of the LCD?
 
Your auxiliary supply is shown as connected line-to-line but referenced to your "ground".  I don't see how this works.
 
Perhaps you provide a complete schematic of the circuit you envision and better feedback to you could be provided.
 
One more thing, in the link you provided, note that in Figure 2 the ac voltages being sensed are apparently low voltages from the output of a 3-phase step-down transformer.  Do you have such a transformer in your circuit?  Also note that what is being sensed is the peak voltage of the line and that the circuit is not measuring the ac voltage directly.

您好，感谢UPDATE增加了详细的图表。不，它是电源接地。它是三相（r＝L1，y= L2，B＝L3）图，没有中性。请检查详细图。请检查电路图。R=L1，Y=L2，B=L3 440V/50Hz请检查电路。我在电路中没有使用任何变压器。基本上它是一个现有的电路。我只能做编码部分。在编码部分，我必须测量两个ADC通道的三个电压。但我坚持这样做，所以我尝试连接另一个通道（第三通道）电阻R4，R5到引脚10的MCU。但这也失败了。[我不知道原因]。所以，还没有成功。无论如何，是否要从其他两个阶段测量三个阶段？或者其他任何建议。



      以下为原文

    Hi,
 
Thanks for update
 
 

I have added detailed diagram .
 

No It's Power Supply Ground . It's Three Phase (R = L1, Y = L2, B= L3) Diagram Without  Neutral. Please Check detailed diagram.

Please Check Circuit diagram.
 

 
R = L1, Y = L2, B= L3  440V/ 50Hz 
 

 
Please check Circuit .
 

I am not using any transformer in my Circuit.
 
Basically it's a existing circuit. I have to done coding part only. In Coding part I have to measure three voltages from two ADC Channels .  
 
But I was stuck to do this so I have tried to Connect another channel (Third channel)  with Resistance  R4 , R5 to Pin 10 of MCU. But this also fails. [I don't recognise the reason] .
 
So,Not Succeeded Yet .
 
Is there anyway to measure Three Phase from other two phases ?
 
Or any other advice.
 
*TS9*
 
 
 
   Attached Image(s)

嗨，图9中的图表看起来丑陋和危险。你真的建立并连接了这个电路到任何活着的东西吗？希望标有接地符号的连接没有连接到盒外的任何地方。如果用文本Vss替换所有这些符号，看起来就不那么挑衅了。在图的电源部分，有从R相到D1和D4二极管的直接连接。在LM78稳压器上，使测量电路电位以R相为基准，其余两个信号在230V德尔塔系统中从+325V到-325V变化，在400V Y系统中从+560到-560V变化，测量电流为0.42mA。晶体管R6和R7，这只能给出+0.42V和-0.42V的电压，对于任何类型的精度来说都太低了。为了避免PIC16中的ESD二极管的电流引起的问题，在到达ADC之前，可以小心地用肖特基二极管对信号进行修剪。而且，信号将负一半。在PIC16F中的ADC无法测量时间。一种可能性是，用每个10kOhm到Vcc和10kOhm到Vss的2个电阻器替换R6和R7，因为给出Vcc/2ADC输入电压的中点值的偏置网络然后在每个正弦周期中在2.5+2.1V和2.5-2.1V之间变化。将电压耦合到微控制器中，可以计算一段时间内所有样品的平均中点值和RMS值(Vadc-Vmid)；和+=(Vadc-Vmid)**2；。RMS=Sqrt(求和/n)；对于#9这样的电路，程序开发和调试有其自身的挑战。在错误的时间将程序员/调试器工具连接到电路上，很可能会破坏该工具和计算机，以及损害您的健康。公司做着和你想的一样的事情。有专门的芯片，以及专门为电力计量而设计的预编程设备，包括单相和三相测量，电压，电流，有功和无功功率。你可以学习数据表和应用说明。在微芯片网站上的标签，看看它们是如何使用的。导航到应用&电力监控…问候，Mysil



      以下为原文

    Hi,
Diagram in message #9 look ugly and dangerous.
Have you really built and connected this circuit to anything live?
 
Hopefully, connections marked with the ground symbol is not connected to anything outside the box.
If you replace all these symbols with the text Vss, it would look less provokative.
 
In the power supply section of the diagram, there is a direct connection from the R phase to D1 and D4 diodes and from there to LM78 regulator,
This will make measurement circuit potential anchored with R phase as reference. 
The two other signals will then either vary from +325 to -325 V in a 230 V Delta system, 0.23mA
or from +560 to -560 V in a 400 V Y system, giving a measurement current of 0.42 mA.
With 1 kOhm resistors R6 and R7, this will only give a voltage of + 0.42 V and -0.42 V,
far too low for any kind of precision.
To avoid problems caused by current in ESD diodes in the PIC16, you may take care to clip the signals using shottky diodes before reaching the ADC.
Also, the signal will go negative half the time, and the ADC in a PIC16F cannot measure that.
 
One possibility could be to replace R6 and R7 with 2 resistors each:
10 kOhm to Vcc and 10 kOhm to Vss, for a bias network giving a midpoint value of Vcc/2 
ADC input voltage would then vary between 2.5 + 2.1 V, and 2.5 - 2.1 V in each Sine period.
Sampling the voltage in microcontroller,
you may calculate average midpoint value and RMS value of  (Vadc - Vmid); 
    Sum +=  (Vadc -Vmid) **2;   for all samples in a period.
    RMS = Sqrt( Sum / n);
 
Program development and debugging for a circuit like #9 have its own challenges.
Connecting a Programmer / Debugger tool to the circuit at the wrong time, could well destroy the tool and your computer, as well as beeing harmful to your health.
 
Microchip do deliver components to companies doing things similar to what you are thinking about.
There are specialized chips, and preprogrammed devices made specifically for Power metering,
both single phase and three phase measurements, voltage, current, active and reactive power.
You could study datasheets and application notes available on Microchip website,
to see how they may be used. Navigate into Applications > Power Monitoring ...
 
Regards,
   Mysil
 

是的，我也用过470K/1K分频器，不过在ADE7754或类似的芯片上，有一个24位ADC，其精度要高得多。当然，其余的都适用。



      以下为原文

    Yeah,
I used 470K/1K dividers too, but on ADE7754 or alike chips that have a 24bit ADC yelding a much higher precision.
All the rest applies, of course.

嗨，Mysil，谢谢你的更新…请看我的回答。我相信你有三相系统的经验，我可以解决我的问题。是的，我用实际硬件制作了电路。不，接地符号没有连接到盒外的任何东西。是的，请检查附件。我的R相读数太低。在这个阶段读数不正确。我不知道这是为什么？所以我已经从Sch.and I t Real Hardware中删除了这个。我使用的是没有中性的三相三线制系统。但是为了改变电压，我在各个相w.r.t neutral(R-N,B-N,Y-N)之间使用3个单独的调光器(用于上下电压)。IMME送入我的硬件。无论如何，有没有测量来自其他两个相的三个相电压？或者用相同的拓扑硬件正确地测量R。因为我以前的硬件工作正常，所以以前的代码[由其他人开发]，或者就像从两个ADC通道获得的读数与任何10位ADC MCU的排列或组合一样？谢谢MysIL再次支持我。



      以下为原文

    Hi Mysil, Thanks for your Update... Please See my replies . I am sure you have experience on Three Phase System and I can solve my problems.  Yes, I have made the Circuit in Actual Hardware.No, ground symbol is not connected to  anything outside the box.Yes, Replaced Please Check attachment.My R Phase Reading is too low.Reading is not correct at this phase .I don't know why this ?. So I have deleted this from Schematic and It Actual Hardware.I am using 3-Phase 3- Wire system without Neutral.But to Change the Voltages I am using 3 individual Dimmer (For Up Down Voltage ) between  individual Phase(s) w.r.t Neutral (R-N,B-N,Y-N).Check Image for my setup and then Middle of the Dimmer Fed to My Hardware. Is there anyway to measure Three Phase Voltages from other two phases ?or to measure R Correctly with Same Topolgy Hardware. Because  my previous hardware is working fine the previous code[Developed by  some other person].or It's Just as Permutation or Combination of Readings Getting from two ADC Channels with any 10-bit ADC MCU?  Thanks  Mysil for bearing me Once again.  *TS9*   Attachment(s)

attachmetns.zip (122.36 KB) - downloaded 268 times

嗨，在没有中点（中性）连接的三相系统中，你可以做你已经做的事，参照R测量B和Y相。另一种方法是使用电阻网络建立虚拟中点，或者如果负载具有中点连接。“R相读数太低。”由于电源的布置方式，R相的测量最多只能测量供电的电压，大约(V(ZD1)+V(D1)或V(D4)，每半个交流周期都会发生变化。这会导致蓝相和黄相的测量值有些失真。使用R相位测量来调整B和Y的读数。另一种可能性是重新安排电源：将电源Vss直接参考到R相位，从Y相位馈电二极管桥，就像现在一样，从B相位馈电。这将需要在馈电桥式整流器的两根导线上都装有高压电容器。通过像你这样的测量，通过减去由AN0和AN1测量的ADC值，可以计算Y和B之间的电压。附图中的电路图仍然没有显示要提供的电阻网络。对ADC电压的正偏压AN0和AN1 .问候，Mysil



      以下为原文

    Hi,
In a three phase system without a midpoint (neutral) connection,
you may do what you are already doing, measure B and Y phases with reference to R.
An alternative is to  establish a virtual midpoind by use of a resistive network, or if the load have a midpoint connection.
 
"R phase reading is too low" 
Because of how the power supply is arranged, measurement of the R-phase will, at best, measure the voltage feeding the power supply,  approx( V(ZD1) + V(D1)),  or V(D4), changing for each half period of AC.
This is causing some distortion in measurement values of phase Blue and phase Yellow.
You might use measurement of R-phase to adjust readings of B and Y.
 
Another possibillty will be to rearrange the power supply: Reference the power Vss directly to R phase,
feed the diode bridge from Y phase, as now, and from B phase. This will need high voltage capacitors in both wires feeding the bridge rectifier.
 
With measurements like you do, it is possible to calculate the voltage between Y and B, by subtracting ADC values measured by AN0 and AN1.
 
Circuit diagram in attachments, still do not show a resistor network to provide positive bias to ADC voltages AN0 and AN1.
 
Regards,
   Mysil

你好，Mysil，再次感谢你所有的方法，我选择下面，因为这里我需要做较少的硬件变化。但我必须使用哪一点测量R相电压1)V(ZD1)+V(D1)或2)V(D4)根据附加电路然后馈送到ADC通道。我不能得到这个。请检查附件并指导我。我已经在示意图中提到了“A”点和“B”点。再次感谢您宝贵的时间。--TS9



      以下为原文

    Hello Mysil,
 
Thanks Again
From All your methods, I select below Because In this I need to do less changes Hardware.

 
But which point I have to used for measurement of R Phase voltage  
1) V(ZD1) + V(D1) or
2) V(D4) according to attached Circuit then fed to ADC Channel.
 
I am not getting this. Please check the Attachment and guide me.
I have mentioned point 'A' and point 'B' in Schematic.
 
Again Thanks for your Precious time...
 
 
--
TS9
 
   Attached Image(s)

您可以使用任何PIC单片机的三ADC，并使用降压变压器降压电压。



      以下为原文

    You can use three ADC's of any pic microcontroller and use step down transformer to step down voltage

这是一个降压电路图。



      以下为原文

   
This is a circuit diagram to step down voltage

为什么不呢？



      以下为原文

    Why not?

 

没有人能看到Nokolay的形象。尝试imgur.com



      以下为原文

    No-one else can see that image Nokolay. Try imgur.com
 

老实说，我也看不见这个形象。可能是这些吗？http://my .mail /ru/mail / NIKOLAYAYPO／Posi/Tea/ 1690。



      以下为原文

    Honestly, I can't see the image too. May be these?
https://my.mail.ru/mail/nikolay_po/photo/tech/1690.html
https://content-7.foto.my...lay_po/tech/b-1690.gif

在VSS相位，你将看不到交流振幅。但是相位之间的相位电压的测量是正确的。



      以下为原文

    You will see none AC amplitude on Vss phase. But the metering of phase voltages between the phases will be correct.