In this video I will explain how ZMPT works and what type of output voltage and waveform we can expect We can connect this module with MCU such Arduino and measure AC mains voltage
Is there any direct library for this so that we can easily select the component from proteus?
@azmrblack
10 ай бұрын
It's not using 2 opamps, it's using 1 physical. 1A and 1B are notated, note the pins too - there is also not 2 opamps on the board. They just split the schematic for easy reading for the 2 opamps inside the 1 chip. Don't know if this is what you meant to say...
@anklabs7504
8 ай бұрын
sorry bro those were messed up i made this video during my early college days, I will soon give new voice over and fix all my mistakes lots of comments received for similar things.
@str8upkickyaindanuts289
3 жыл бұрын
Comparator is an opamp in open loop gain (no feedback), neither of the 358's are operating as comparators in the schematic @5:00. Both have a Av = 10, giving a final gain of 100 in the schematic shown. The voltage divider R10 & R11 are used to offset the final output to mid-scale of Vcc, 2.5v in this case. Same is done with R4 & R5 on the input of U1:A. Since the transformer is 1:1 ratio the designer used a resistor R1 to limit current proportionally to the applied input voltage, but the value chosen is rather high for 250Vac giving the need for the high gain in the opamp stage. With better consideration for the value of R1, we could set the resistance to net 20% rated current of the transformer so that the burden voltage resistor R2 can be chosen. With careful selection of these components the need to amplify could be mitigated to a single voltage follower (unity gain buffer) to lower the noise floor seen at the ADC input. The 820K R1 sets the primary current to 431uA @250Vac, which is orders of magnitude lower than the rated current of the transformer giving the need for amplification. If R1 = 7k the transformer current is 50mA @250Vac, with R2 = 100 Ohms the resultant burden voltage of 5vp-p would represent 250Vac on the input, all while staying within the specifications of the transformer and without the need for amplification which would inherently add noise. SAFETY WARNING: This module is somewhat dangerous IMO, the full input voltage is applied across a single SMT package resistor which likely is out of spec for that package due to size alone. Ideally one would use a series connected set of resistors on the primary to minimize the applied voltage to each resistor in order to maintain a safe margin of error. One such solution would be to use a through hole wire wound current limit resistor(s) with a series connected PTC device to achieve a safer layout.
@anklabs7504
3 жыл бұрын
Finally I am very happy someone is correcting I have done dozens of mistake in other videos too when I made this video i can not understand what the circuit is doing even my simulations didn't satisfy me. I asked few people there said it seems to be a comparator. so I said it's a comparator i will try to correct this video. due to excessive noise this module is no use for me i made a diy version which worked perfectly fine but still some safety features were not implemented. I want to know more about you...
@SantoshBhagwat1976
3 жыл бұрын
Well understand 👍👍
@hafsaahmed_abbas6991
11 ай бұрын
how you have calculated limiting and sampling resistors value
@pkp8559
2 ай бұрын
what is the benefit of using current transformers instead of stepdown transformer. any one practically tested with oscilloscope? to check lag between input and output. thanks
@str8upkickyaindanuts289
2 ай бұрын
@@pkp8559 A current transformer is for measuring current using the magnetic field generated by current flowing through a wire. While a step-down transformer can be used for measuring the voltage, but it's honestly not ideal due to the transfer function of the transformer being frequency dependent. Every lab instrument uses a very high resistance voltage divider for this task due to the frequency independence of the resistive divider. Obviously this is within reason as the parasitic inductance and capacitance start to play a factor when dealing with high frequency signals. Your second question is irrelevant and seems based on the misunderstanding of the previous question.
@jacobmalichy739
Жыл бұрын
Hello what are the parameters for the transformer in the zmpt101B voltage sensor
@anklabs7504
8 ай бұрын
sorry i forgot the details - and now a days i don't have much time to quickly update it here. but try asking Chat-gpt well AI is replacing humans faster. Because it will take me longer. and Yes when i made this video i dint find a proper data sheet so i had to find things in Hard way and didn't cover everything in this video
@SantoshBhagwat1976
3 жыл бұрын
I have also experience the same problem.
@npslucknow9235
2 жыл бұрын
How can i measure 350V ac sir ?
@anklabs7504
2 жыл бұрын
It's should be possible but not tested, with ZMPT, if you like to use transformers as shown in part 2 you have to find suitable transformers which can handle 350 volt and change the circuit, my schematic have some bugs, You can try voltage divider method but be careful and try to use 5-10 watt resistors
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