Wireless Energy Meter

[Jeffrey Peter]

Im currently designing a wireless energy meter for my final year project..... I would like to know what kind of RF transmitter to use and its frequency for a range(min 15 meters).... then which is the Best online shop to get the components ?? In this project I though of using ADE7757 but I don't know where to buy it ?? Thanks in advance........

 

[tpetar]

Did you make circuit and firmware for your project ? Where You stuck ?

For RF you can use 433MHz modules OOK,FSK or similar, range can be up to 100m.



Where to buy parts, best is at your place in your country to avoid transport costs. You are probably UK/US then there is no problems for you, you have good coverage in market with semiconductor dilers/distributers.


https://www.digikey.com/
https://www.rs-online.com/index.html
www.tme.eu

 

[Jeffrey Peter]

Actually this topic was given to me last week... till now I searched online but I could not find how to fix frequency for the rf transmitter.....

 

[tpetar]

Did you make RF TX or you buy it ?

 

[pico]

For Frequency to use check this

https://en.wikipedia.org/wiki/ISM_band

 

[Jeffrey Peter]

I want to buy a RF TX ......but I don't know what frequency or power to use.

 

[tpetar]

Buy standard 50mW-100mW 433MHz.

Consider 1mW per 1m on open. 433MHz is free band.

You should choose adequate modulation according your application.

 

[FvM]

Buy standard 50mW-100mW 433MHz.
Consider 1mW per 1m on open. 433MHz is free band.

Generally you need to know the RF regulations of your country. 433 MHz meter reading applications allow 10 mW with max. 10% duty cycle in the ETSI domain. In the U.S., you better use 900-928 MHz band because 433 MHz is restricted to very low power (about 50 µW).

Range is much larger, however. 10 mW is good for several 100 m outdoor and several 10 m inside a building.

 

[Jeffrey Peter]

I have to transmit about 2kb.... what about the modulation technique ?

 

[FvM]

You should refer to RF modules or chipsets with digital data interface (SPI or UART). FM is more reliable than AM.

Alternatively RF modules with built-in network support, e.g. ZigBee or Bluetooth, can be an option.

 

[Jeffrey Peter]

Wat about FSK ? can we use it...

 

[FvM]

FSK would be subsumed with variants like GFSK under FM. FSK is in fact commonly used for low and medium speed digital data transmission up to several 100k, e.g. by the Chipcon/TI transceivers chipsets CC10xx and CC11xx.

 

[Jeffrey Peter]

Is normal Frequency modulation is enough or I have to go with Frequency Shift keying... which is advisable

 

[FvM]

If your modulation signal is digital (0/1), "normal FM" turns into FSK. If you apply a gaussian low pass filter before, you get GFSK. More complex digital modulation methods are transmitting multiple bits in one "symbol", e.g. 4FSK.