Careful you might start a bidding war with a consequent race to the bottom. Just let this one go.

My bid will be much higher than your bid.

 

Described in National Semiconductor application note #222

 

My bid will be much higher than your bid.

In a pig's eye.

 

In a pig's eye.

My price would include the whole pig! Not just the eye.
Really, though, it would be a no-quote because of the inability to establish adequate communication with the requester.

 

My price would include the whole pig! Not just the eye.
Really, though, it would be a no-quote because of the inability to establish adequate communication with the requester.

In the business we prefer to never say no directly to a customer. We say no by making him an offer he can refuse.

 

boostbuck
thank you Sir .
for you help - I did not know about the MPPT - seriously i have contacted the IC suppliers and no help
for my watt meter project and i also search google no help ..
your respect Sir please how can we get to use AC volts and current

boostbuck
thank you Sir .
for you help - I did not know about the MPPT - seriously i have contacted the IC suppliers and no help
for my watt meter project and i also search google no help ..
your respect Sir please how can we get to use AC volts and current

ok: I appologize its a watt meter to measure current and voltage through diode's as being measured on zero balancing Wheatstone bridge
thank you Sir === lowest voltage say 1 volt dc/ac low current up to depends upon measure diode 5 Amps with a suitable DC/AC supply say 12 volts rough quotes

 

Measuring voltage and current through a device being tested in a bridge circuit is not a typical test at all. In fact, checking a diode in a bridge circuit is rather unusual, really.
What diode property is being tested for? Normally other circuits are used for finding diode properties, usually some variety of curve tracer is used. So can you explain more about what the test is seeking to learn about the diode function?

 

i thought that allabout circuits
i would be given help - this was post several weeks bavck still no help nore no advice
respectfully TERENCE UK

 

Not until post #26 did we get any mention of the application of the wattmeter, AND then we find that it is to measure current and voltage through a diode being tested with a bridge circuit. Diodes are not tested using bridge circuits, they are tested with a ystem usually called a curve tracer, which usually varies the voltage and measures the current. This may be done with different rates of change to determine the diode response time. Wattage may sometimes be calculated, but not for most applications.
So what is the benefit oof using a self-balancing bridge for the test?

 

i thought that allabout circuits
i would be given help - this was post several weeks bavck still no help nore no advice
respectfully TERENCE UK

I asked you for some information on the required resolution and speed of response of the power measurements in posts#10, #13 and #18. All you did was repeat the minimum and maximum voltage and current. If you do not understand what those are or why I asked for that information, I can not answer your question because you would not understand the answer.

 

i thought that allabout circuits
i would be given help - this was post several weeks bavck still no help nore no advice
respectfully TERENCE UK

To get assistance with a problem, or answers to a question, one needs to provide enough information for us to understand the whole thing. That is quite a bit different from asking for the complete design of a fairly complex piece of measurement equipment. The Fluke company and the Beckman instruments company, among others, sell some very good digital wattmeters that could include the functions that you seek. Those instruments would offer the vary big benefit of being accurate and durable. So really you are seeking the design information for a rather expensive device, for free. That is not what this forum is all about.

I am wondering if this search is for some school work or for a job or for personal use. There is a section just for school questions someplace in this site.

 

its to match unknown diode and rectifier diodes using the bridge method
this is an idea I had and measure the wattage of the set up

To get assistance with a problem, or answers to a question, one needs to provide enough information for us to understand the whole thing. That is quite a bit different from asking for the complete design of a fairly complex piece of measurement equipment. The Fluke company and the Beckman instruments company, among others, sell some very good digital wattmeters that could include the functions that you seek. Those instruments would offer the vary big benefit of being accurate and durable. So really you are seeking the design information for a rather expensive device, for free. That is not what this forum is all about.

I am wondering if this search is for some school work or for a job or for personal use. There is a section just for school questions someplace in this site.

==================================================
I am On a very low weekly Pension --what you are suggesting out of the question
I must work with what i do have at moment not a lot !!
Terence

 

its to match unknown diode and rectifier diodes using the bridge method
this is an idea I had and measure the wattage of the set up

==================================================
I am On a very low weekly Pension --what you are suggesting out of the question
I must work with what i do have at moment not a lot !!
Terence

OK, matching power diodes could most easily be done by putting them in series and mmeasuring the voltage drop across each diode as the current was increased. That operation can easily be done with an older computer with an analog input board and a variable current source, if you did not want to make it fully automated. It would take as much as a second to record each data point, depending on the computer speed and the switching scheme. Long ago the company I worked at did a comparable set of measurements with a PCXT. My point being that it will not need a state of the art computer to do this test. If you could add three isolation amplifiers the switching setup would be much simpler and the test time would be much less.
The results could be a plot of the diode's forward voltage drop versus current for each diode, in just a very few seconds. Plotting the reverse leakage current versus reverse voltage could be very similar, but with different current and voltage measurement ranges.
So there you have a description of the test system and an explanation of what it will require. I hope that it is a bit useful.

 

To get assistance with a problem, or answers to a question, one needs to provide enough information for us to understand the whole thing. That is quite a bit different from asking for the complete design of a fairly complex piece of measurement equipment. The Fluke company and the Beckman instruments company, among others, sell some very good digital wattmeters that could include the functions that you seek. Those instruments would offer the vary big benefit of being accurate and durable. So really you are seeking the design information for a rather expensive device, for free. That is not what this forum is all about.

I am wondering if this search is for some school work or for a job or for personal use. There is a section just for school questions someplace in this site.

===============================================
personal electronic work project
as I AM a pensioner on little weekly pension I must work with what i do have ''thats not a lot ''
first it was whetstone bridge to match ton's on unknown signal diodes and rectifier diodes
then I thought of a zero balance meter across that whetstone bridge( then Thought measuring
the voltage to log then I thought measuring the current -- equals watts....
This is across the two arms of that whetstone bridge ..
This brings me to the watt meter ...
I thought if I can measure the current 0.5 mA up to 5 Amps and DC volts 0.5volts up to say 50 volts
then use IC's convert into Watt's to read on & segment display ...Hence DC volts and current //AC volts and ac current { + RF)

 

I am not aware of watts being aociated withdiodes, except as a power rating. Forward voltage drop at some current and revers leakage current and reverse breakdown voltage, for some types, at some reverse voltage. So while the voltage and current readings seem reasonable the wattage readings would serve no purpose. So yes, you can calculate watts but what value will that number provide?

 

I am not aware of watts being aociated withdiodes, except as a power rating. Forward voltage drop at some current and revers leakage current and reverse breakdown voltage, for some types, at some reverse voltage. So while the voltage and current readings seem reasonable the wattage readings would serve no purpose. So yes, you can calculate watts but what value will that number provide?

Sir
respectfully -- This was about balancing in bridge to match all odd signal diodes and same for rectifier Diodes - then I wanted a zero meter to tell me when bridge is balanced that's when I thought of a simple ac/dc voltage/current watt meter (( Yes I know when Bridge is Balanced no current flows))..
current will still flow in each leg of the Bridge: that's what i do want to measure AC/DC Volts/AC/DC Current =Watts.
I have got 100's signal Diodes no markings and same rectifier Diodes these need sorting out before being able to use them ...

 

I am not familiar with bridges being used for any portion of diode testing. Certainly a bridge may work for some checks of diode properties, but as diodes are nonlinear devices it would be a challenge to understand the results. And it is not clear how one of the quite important characteristics, the reverse breakdown voltage, could be measured using a bridge.
Many semiconductor manufacturers have previously published detailed descriptions about how they measured the parameters on their specification sheets, and I suggest reading those publications, which ought to be available in a decent library. They will not be in the new literature section, since many of them were published in the 1970's era. They will include the information that you need to understand.
The major parameters that determine the suitability of a diode for an application are forward current capability, reverse leakage current and breakdown voltage, switching time, and junction capacitance. There are other parameters as well, but these are the primary ones. I am not sure how you would even measure them with a bridge circuit.

 

I am not familiar with bridges being used for any portion of diode testing. Certainly a bridge may work for some checks of diode properties, but as diodes are nonlinear devices it would be a challenge to understand the results. And it is not clear how one of the quite important characteristics, the reverse breakdown voltage, could be measured using a bridge.
Many semiconductor manufacturers have previously published detailed descriptions about how they measured the parameters on their specification sheets, and I suggest reading those publications, which ought to be available in a decent library. They will not be in the new literature section, since many of them were published in the 1970's era. They will include the information that you need to understand.
The major parameters that determine the suitability of a diode for an application are forward current capability, reverse leakage current and breakdown voltage, switching time, and junction capacitance. There are other parameters as well, but these are the primary ones. I am not sure how you would even measure them with a bridge circuit.

The Balance Bridge purpose to match as close to each other as possible Diodes and or rectifiers
saying that -- still must have curtain voltage and current to turn on the Diode/Rectifier to be able
to zero out the the unknown to the testing Diode/Rectifier to find the Balance between unknown and its sample ..
Therefore you must be able to measure the used DC/AC volts and or current thats where Watt meter happens...
I thought as I was measuring those AC/DC Volts and current ----I would turn these measurements into Watts !!!!
That's easy said than done.....
Respect to all >>> thank you for all your supports

 

The scheme you are considering, using a bridge with high voltage an current available to distinguish signal diodes from rectifier diodes should work very well, because, after testing, all the signal diodes will be destroyed.

 

The scheme you are considering, using a bridge with high voltage an current available to distinguish signal diodes from rectifier diodes should work very well, because, after testing, all the signal diodes will be destroyed.

respect Sir Keith Walker
where don't you get it correct
Diode is roughly 0.6 volt
whetstone bridge is to apply the correct conductive volts on signal Diodes and on rectifier diode
to balance out the bridge using good diode against the testing the unknown = balancing off the unknown Diode/rectifier to get a Balance match using standard Diodes/rectifier Diodes