Does anyone here use the Peak Lcr45? Max Inductance?

[rwgast_lowlevellogicdesin]

I had planned on buying a DE5000 LCR meter, although I had my eye on the LCR45 too. The more I read up on the DE5000 the less impressed I am with it. Apparently it has a horrible user interface. I also want to be able to measure impedance (Z real and imaginary) and the DE5000 does not display a Z value on the screen. Apparently there is PC software for the DE5000 which will give you impedance measurements and all kinds of other cool data. The problem here is #1 you have to buy a $70 cable that seems pretty hard to source or you can DIY a FTDI and phototransistor for much cheaper but without a 3d printer the adapter would turn out physically pretty janky. #2 is the bigger issue, and that is, that the link for the software on DEER EEs web site is broken and I can't seem to find the file download anywhere else. Then I realized the LCR45 actually measures at 200Khz vs the DE5000s 100Khz. The only issue I have with the LCR45 is its form factor and built in test hooks. I have a cart at Amazon full of stuff I need including a new bench supply but I haven't pulled the trigger on it yet because I have not decided on whether I should buy the DE5000 or the LCR45.

I was just about to complete my Amazon order with the LCR45 in cart, but I realized the listed specifications say the max measurable inductance is 2H. I would like to be able to measure transformer windings, and 2H wont cut it for any sizeable power transformer. I read the LCR45 User Manual, and on page 17, it says at a 1khz test frequency you can measure up to 10H. So can this thing measure up to 10H or 2H?? I e-mailed Peak a week ago with this question and have not gotten a reply. Im hoping someone on the forum who has an LCR45 can clear this up for me.

[tautech]

Study this thread and particularly its conclusion:
https://www.eevblog.com/forum/testgear/shannon-st42-lcr-tweezer-test-and-comparison-thread/msg5599769/#msg5599769

[rwgast_lowlevellogicdesin]

Im sorry im kind of confused, that thread seems to be a comparison of different LCR tweezer meters and there accuracy?  I read the first and last two pages, if there was something relevant to my post i either missed it, or it went over my head, either is very possible.

Im just trying to figure out the max possible inductance the peak lcr45 can measure, becuase the listed specs and the user manual differ.  Im not sure if im just missing what your trying to get me to see in that thread? I dont want to use this meter for very much smd stuff, and i try to never make in circuit measurements of component values. Im just looking to get quick measurements of through hole inductors and caps for low freq non RF. Im not even all that concerned with absolute accuracy as long as im in the ball park. But being able to measure transformer windings would be super helpful sometimes! I deal with a lot of transformers that have to documentation.

[Psi]

I have the older peak LCR40.
I can test anything on it if you can think of something.
Presumably if the LCR40 can do it the LCR45 can too.

I have a good selection of mains transformers if you can think of a size/amps rating one you'd like me to test.

[J-R]

I have the LCR45 and it goes up to 10H in the 1kHz setting.

Side note, the LCR45 is annoying to use, so get the DE5000 as well.

[rwgast_lowlevellogicdesin]

Well that is good to here, im pretty sure 10H is enough for most transformers 1kva and under. What makes the LCR45 annoying to use?

[J-R]

In general, I find PEAK's products frustrating to use primarily due to their odd size/shape, the two-button interface and the test lead setup.  Some other gripes are their inconsistent battery and backlight choices.

Quick example of "annoying": to change the test frequency on the DE-5000 it's a single, clearly-labelled button to cycle through the choices, while on the LCR45 you're having to run through half a dozen button presses each time you want to change it.

[Martin72]

I would like to be able to measure transformer windings, and 2H wont cut it for any sizeable power transformer.

But being able to measure transformer windings would be super helpful sometimes!

Well that is good to here, im pretty sure 10H is enough for most transformers 1kva and under.

What exactly do you want to measure on the transformers and for what purpose?
And are you talking about "normal" 50/60Hz transformers, or also some for switched-mode power supplies?

[rwgast_lowlevellogicdesin]

Alot of unkown 60hz power transformers. Mostly to calculate winding ratios. Im hoping it can help me figure out the windings on switchmode transformers too. Idk if the peak would be good for this but id also like to use its ability to calculate Z to check out some impeadence matching transformers for audio/tube etc.

[Martin72]

I'll write something about how we measure transformers later.
But here's a quick test from just now, I took out a transformer of my choice and measured it once with the ST42 tweezers, then with the ET3503 measuring bridge.
The tweezers can output a maximum of 500mVpp (178mVrms) and at least 100Hz.
The ET3503 measuring bridge can be set to almost any value, the result is the same (2.78H).
But the ET3503 can do even "more", see further pictures.
The inductance of the transformer changes with the frequency, but also with the level at the same frequency.
As I said, later I will write how we measure transformers, an LCR is not used, or rarely.

[rwgast_lowlevellogicdesin]

I had no idea the voltage effected inductance that much! If your just measuring windings to get there to calculate there ratio yo each other i wouldnt think the absolute measurements would matter?

[Martin72]

You would have to try it out, I can do it tomorrow, then also with an Atlas LCR, but also div others at work.
The ratio between primary and secondary windings is best measured with a voltage supply.
For example, you feed in 50Vac primary, if you then measure 5Vac secondary, you know the ratio (1:10).
If you want to know the number of windings, you have to determine at least one side, the other results from the ratio(or measure it too).
Only works with non-potted transformers:
-Loop a wire around the core (equal to one turn).
-Apply voltage to the winding of which you want to know the number of turns.
-Measure the voltage on the one wire.
-Example: Supply 20Vac to the winding, measure 100mV on the one wire = 200 turns.
-Polarity test:
Measure voltages with an oscilloscope, 1 channel primary, 1 channel secondary, view phase relationship.
And so on...

[Grandchuck]

I had no idea the voltage effected inductance that much! If your just measuring windings to get there to calculate there ratio yo each other i wouldnt think the absolute measurements would matter?

Shown below is another example at 0.1V, 0.5V, and 1V at a frequency of 100 Hz.  At 10 kHz, there is much less variation due to excitation voltage and the readings are all around 8 H.

[rwgast_lowlevellogicdesin]

When you buy a standard inductor, and it is idk 10microHenerys lets say, how do they get that number. I know that there usually tested at 100khz or whatever but what is the standard voltage used?

I really wish there was something like the Bode frequency analyzer at a reasonable price. Once you get to RF and everything is 50ohm and you can use a VNA measuring this stuff is so much easier. I will probably never need to wrap or use an inductor in a circut using 2v or less.

Lets say im working on a 50v 500khz boost converter and i need to wrap a 10microHenery as part of the circuit, is there any way to test my inductor without breaking the bank. At this point i feel like there are a lot of situations where you just pick a core material use a winding calculator and call it a day!

[Martin72]

When you buy a standard inductor, and it is idk 10microHenerys lets say, how do they get that number. I know that there usually tested at 100khz or whatever but what is the standard voltage used?

It is usually stated in the data sheet how the measurements were taken.
So with chokes, transformers have to be assessed differently again.
With normal mains transformers, inductance is more of a nice to know.
With high-frequency switching power supply transformers, the situation is different, depending on the topology used.

[rwgast_lowlevellogicdesin]

The only reason im leaning tword the lcr45 is becuase it will give you an imedance reading. I can not find a meter under 200 bucks that does that. Is there an easy way to calculate Z using the info given on most any handheld meter? I just noticed the lcr45 doesnt have any frequency options under 15khz so thats now a no go.

[Martin72]

I can not find a meter under 200 bucks that does that.

Oh yes, there are some who can.
Among the "prominent" ones are the DE5000 or ET44xx from East Tester, but also the ST42 measuring tweezers.

Is there an easy way to calculate Z using the info given on most any handheld meter?

This requires the exact measurement frequency and then conversion (e.g. XL= 2*pi*f*L)
And the RDC value for the real component of the impedance.

[rwgast_lowlevellogicdesin]

Well i figured out the meter i intend to buy after a lot of looking! An east tester et42, it does bias voltage, and calculates Z. For 200ish it seems like the most feature packed meter you can get! I dont understand why Z is omitted from most of these meters, its not like Z requires any hardware the de5000 doesnt have, its much more helpful than esr in my opinion. I mean the de5000 apparently does calculate Z but its only displayed in the desktop app that has a broken link and requires an overpriced and at this point rare cable. The ir cable for my fluke 289  costs less lol.

At some point i aspire to build a desktop impeadence analyzer/lcr that will measure a few mhz at higher voltages, i even ordered all the math books i need to help  catch me up but for now i just need something to fill in the info i cant get from bode plotting. In the world of great dds chips and cheap fpga/200mhz micros i cant figure out why there isnt anything like the Bode FRA for 500 bucks.

[egonotto]

When you buy a standard inductor, and it is idk 10microHenerys lets say, how do they get that number. I know that there usually tested at 100khz or whatever but what is the standard voltage used?

I really wish there was something like the Bode frequency analyzer at a reasonable price. Once you get to RF and everything is 50ohm and you can use a VNA measuring this stuff is so much easier. I will probably never need to wrap or use an inductor in a circut using 2v or less.

Lets say im working on a 50v 500khz boost converter and i need to wrap a 10microHenery as part of the circuit, is there any way to test my inductor without breaking the bank. At this point i feel like there are a lot of situations where you just pick a core material use a winding calculator and call it a day!

Hello,

with the Analog Discovery (3) this works reasonably well.
I have used a 1 uH coil.

With a generator and a scope (with average) and some software, this is also possible.

Best regards
egonotto

[Martin72]

Today I measured a small transformer with the Peak LCR, once with the LCR40 and then with the LCR45.
First LCR40...

[Martin72]

The LCR45...