Power analyzer using arduino

[s.aryanpour]

thanks barddya

yes i know about c and basic language

but i don't know how to calculate my parameter

[Nathan_B.]

There are a lot of resources that you can find online on how to calculate

such parameters.

[s.aryanpour]

but i can't find

maybe i'm not good at searching or maybe i'm not clever 

[barddya]

Tryhttps://www.youtube.com/watch?v=9ogLqX5uFfM

Be

From: s.aryanpour <web.community@ni.com>

To: barddya <barddya@yahoo.com>

Sent: Monday, November 9, 2015 9:20 PM

Subject: - Re: Power analyzer using arduino

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NI Community

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Re: Power analyzer using arduino

created by s.aryanpour in LabVIEW Interface for Arduino - View the full discussionbut i can't findmaybe i'm not good at searching or maybe i'm not clever 

Reply to this message by replying to this email -or- go to the message on Community Start a new discussion in LabVIEW Interface for Arduino by email or at Community

[iffi444]

Can I use NI myDAQ for a single phase power analyzer becase it has aslo 2 analoge input with sample rat 200KS/s which I think will be very appreciated for my work

[hrh1818]

The NI MyDaq is a better choice than an Arduino Uno or Due for use as a single phase power analyzer.  It is compatible with bipolar inputs as it has plus and minus 10 volt analog input range.  Whereas an Arduino Uno has unipolar 0 to 5 volt analog input range. As far as I can tell the NI MyDaq has only one analog to digital converter.  Ideally to measure power you would like to have dual simultaneous analog to digital converters.  However, with a 200k samples per second conversion rate there will only be about  0.1 degrees of phase shift error introduced by the difference in sampling times for a 60 cps power line frequency. It definitely will be easier to use Labview with a NI MyDaq than it is with an Arduiuno Uno. or Due

The only limitation I spotted so far is the lack of trigger capability for starting an acquisition sequence.  To make power or RMS measurements you need to sample the signal for an integer number of periods. This is easy to do using a zero crossing detector to trigger a measurement sequence.  An alternate approach is use software to control the sampling rate and use the formula

Number of samples = samples per second  * N * T

T is the period for one cycle.  T = 1/50 for 50 cycles per second power and 1/60 for 60 cycles per second power.  N is the integer number of periods.

See <http://www.ni.com/pdf/manuals/373061f.pdf> for NI MyDaq specifications.

hrbh212

[iffi444]

NI myDAQ has two analog input chanels so has two ADC converter,is im right

[Nathan_B.]

No, one ADC can be used for many channels so having multiple channels does

not mean you have multiple ADCs.

When one ADC is used for multiple channels, it uses multiplexing to be able

to sample each of the channels sequentially. This means that those channels

are not samples at exactly the same time which is to what hrh212 was

referring.

[iffi444]

Its in myDAQ causion
Do not use this module for connection to signals or for measurements

within Measurement Categories II, III, or IV.
so my question is can I use this device for real single phase circuits by providing signals with conditioning circuits

Measurement Category I:
This category is for measurements of voltages from specially protected secondary circuits. Such voltage measurements include signal levels, special equipment, limited-energy parts of equipment, circuits powered by regulated low-voltage sources, and electronics.

Measurement Category II:
This category refers to local-level electrical distribution, such as that provided by a standard wall outlet or plug in loads (for example, 115 AC voltage for U.S. or 200 AC voltage for Europe). Examples of Measurement Category II are measurements performed on household appliances, portable tools, and similar modules.

Measurement Category III:
This category refers to measurements on hard-wired equipment in fixed installations, distribution boards, and circuit breakers. Other examples are wiring, including cables, bus bars, junction boxes, switches, socket outlets in the fixed installation, and stationary motors with permanent connections to fixed installations.

Measurement Category IV:
This category refers to origin of installation or utility level measurements on primary over-current protection devices and on ripple control units.

[hrh1818]

The specifications say "Measurement Category I1 is for measurements performed on circuits not directly connected to the electrical distribution system referred to as MAINS voltage".  Therefor I suggest you use transformers between the Mains circuit and the NI MyDAq.

Use a AC output Wall Wart similar to the following for interfacing line voltage to the MyDaq's input. 

<http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?search_type=jamecoall&catalogId=10001...>

Use a current sensor similar to the following for interfacing load current to the MyDaq's input.

<http://www.seeedstudio.com/depot/Noninvasive-AC-Current-Sensor-30A-max-p-519.html>

hrh212