Bench LCR Recommendations?

[mawyatt]

Josh, didn't your meter come with the front and rear rubber bumper guards?

Best,

[KungFuJosh]

Josh, didn't your meter come with the front and rear rubber bumper guards?

Best,

Haha, yeah, I had to remove the bumper guards so both meters would fit under that shelf. I'll eventually make a taller shelf with more stuff going on to organize my bench, and the bumpers might go back on the meters. The thing is that I'm tempted to put the SDG2122X on the bench too if I can come up with a reason to need a better AWG than what's on my scope. I was considering setting up a rack, but I dunno if I'll go that route. I kinda like the way the stuff is now.

[KungFuJosh]

I tested a bunch of guitar pickups, I really like this meter. I used Ls-Rd for L and DCR at 100Hz, then switched to Cs at 100kHz. Much simpler workflow than clunking through the DE5000.

Here's a couple of them.

Pickup 1:
DE5000:
4.11H
7.493kΩ
126.98pF

TH2830:
4.10479H
7.47774kΩ
143.844pF

Pickup 2:
DE5000:
3.578H
8.08kΩ
128.59pF

TH2830:
3.57755H
8.05381kΩ
128.415pF

[KungFuJosh]

I ordered some generic kelvin clips from ali. I tried one set on the TH2830 and compared them to the TH26011CS.

I made an exciter coil to test guitar pickups with an AWG and scope. This is the coil being measured (on the TH2830).

TH26011CS:
Ls 22.9412μH
Rd 117.879mΩ

Generic:
Ls 24.4134μH
Rd 116.482mΩ

That's not too bad. So I chopped the cable and converted the TL-22 to kelvin clips for the DE5000.

Tested a "tropical fish" film capacitor, 1kHz, 1V.

DE5000:
Kelvin:
26.2nF
21.1Ω (stable)
TL-21:
26.2nF
18.8Ω (unstable)

TH2830:
TH26011CS:
26.1860nF
22.7711Ω

And now the DE5000 can go back to living in the meter drawer.

[The Electrician]

When I click on your spreadsheet results in reply #47 I only see a picture of your DE5000.

The results from a DMM for the value of an electrolytic is not really comparable to the results from an LCR meter.  See this thread: https://www.eevblog.com/forum/testgear/about-capacitance-measurement-with-dvms/msg489690/#msg489690

[KungFuJosh]

When I click on your spreadsheet results in reply #47 I only see a picture of your DE5000.

The results from a DMM for the value of an electrolytic is not really comparable to the results from an LCR meter.  See this thread: https://www.eevblog.com/forum/testgear/about-capacitance-measurement-with-dvms/msg489690/#msg489690

Click lower. 😉

I included the DMMs only because that was an improvised reference set of caps to see if my meters drift over time. I figured I might as well include the DMMs in there. I'll eventually do the same thing with a set of resistors.

[The Electrician]

Click lower. 😉

Here's what I see to click on.  If I click on the thumbnail image of the spreadsheet, or if I click on the text description below that, either way I see a picture of your DE5000.

 

[KungFuJosh]

Here's what I see to click on.  If I click on the thumbnail image of the spreadsheet, or if I click on the text description below that, either way I see a picture of your DE5000.

Weird! Maybe your browser cache is messing with you?

That doesn't happen for me.

Anyway, it's the same as the image in the post anyway. You can right-click it and open it in a new window if you want it bigger.

[nctnico]

Those TH2830 / TH2832 look mighty interesting. Only thing they don't have is external DC bias which would be handy to have (up to 25V or so).

[KungFuJosh]

Those TH2830 / TH2832 look mighty interesting. Only thing they don't have is external DC bias which would be handy to have (up to 25V or so).

Don't worry, Mike has a project for that 😉:

Also consider building the DC Bias adapter, details here.

https://www.eevblog.com/forum/projects/bias-network-for-lcr-meter/

I've only ever tested at 1V. Can somebody enlighten me to a situation that higher voltage would be helpful?

Thanks,
Josh

[Martin72]

Those TH2830 / TH2832 look mighty interesting.

Yes, the devices from tonghui/sourcetronic fill a gap between the very cheap ones from e.g. East Tester and the "big" ones from R&S, Keysight.
But also GWInstek, they want to have real money for their bench meters(up to 40000€..).
For a device with 100khz you are then over 2000€(LC6100):

https://www.reichelt.de/lcr-meter-lcr-6100-digital-100-khz-lcr-6100-p176048.html?PROVID=2788&gclid=Cj0KCQjw4NujBhC5ARIsAF4Iv6ff_KhaDAcTg5XskuzXJL9vq7spJnW3kFPT8r6sOFUQJdisplwnWVkaAnZCEALw_wcB

Whereby that is not better, only more expensive. And it looks very similar...
Our "Tonghui" (Sourcetronic) is as already said, very well made and exists for 3 years every external calibration without having to be readjusted.

Can somebody enlighten me to a situation that higher voltage would be helpful?

AFAIK for some types of caps.

[nctnico]

Those TH2830 / TH2832 look mighty interesting. Only thing they don't have is external DC bias which would be handy to have (up to 25V or so).

I've only ever tested at 1V. Can somebody enlighten me to a situation that higher voltage would be helpful?

It is handy for checking whether MLCC capacitors meet their spec and/or how much they vary under DC bias. Selecting the right MLCC capacitor for a circuit can be a tedious job.

[mawyatt]

Those TH2830 / TH2832 look mighty interesting. Only thing they don't have is external DC bias which would be handy to have (up to 25V or so).

I've only ever tested at 1V. Can somebody enlighten me to a situation that higher voltage would be helpful?

It is handy for checking whether MLCC capacitors meet their spec and/or how much they vary under DC bias. Selecting the right MLCC capacitor for a circuit can be a tedious job.

Exactly, one of the many reasons we developed the DC Bias adapter awhile back. This works really well, and with the SMD fixtures also mentioned, one can quickly access how a ceramic cap behaves, or misbehaves

We found even the quality Samsung MLCC vary, mostly due to the ceramic formula utilized tho. Another interesting use is studying the reverse and slightly forward bias PN junction equivalent capacitance vs voltage, and a zener when entering breakdown.

The usual electrolytic and tantalum caps are also worth investigating.

One very interesting topic we haven't seen discussed is investigated the Miller Capacitive effect in bipolar and Mosfet transistors under certain bias conditions, this is on our "to do" list when we get some free time.

Anyway, after some research, we were one of the early adopters of this TH2830, and not disappointed in the acquisition decision awhile back. Now we've developed some plotting routines which produce nice plots, this is icing on the cake

Pretty sure some of the upper tier equipment suppliers are using Tonghui as a source, some of the fixtures look quite similar if not exactly like Tonghui fixtures, except they cost much more  

https://www.eevblog.com/forum/projects/bias-network-for-lcr-meter

https://www.eevblog.com/forum/testgear/cheap-smd-lcr-fixture-the-good-bad-and-ugly

https://www.eevblog.com/forum/testgear/lcr-meter-plot-software



Best,

[KungFuJosh]

Pretty sure some of the upper tier equipment suppliers are using Tonghui as a source, some of the fixtures look quite similar if not exactly like Tonghui fixtures, except they cost much more  

The Tonghui fixtures aren't cheap either though. 🤣

I think the normal price for the TH26007A or TH26008A is around $350, but you can find it for half that (taking the gamble whether it's real or not). The real ones usually have 4 connector levers, the fake ones usually only have the outer 2...still a gamble though.

EDIT: Holy crap, Batman! I just saw what Hioki charges for the same thing. 🤯🤯🤯

[mawyatt]

If you do your research you can find some genuine Tonghui fixtures at reasonable prices, we got TH26009B Tweezers that are OEM. We don't use them very often, altho they are good to 15MHz!!

Yep, the Hioki equipment is expensive, thankfully all the Tonghui fixtures fit and work fine on the IM3536, we made absolute sure of that before ordering

The cheaper no-name SMD fixtures seem OK, especially if you check out, tighten and mod them as we've shown. We fooled around with one and tried to see if we could use it for temperature sweeps by raising the plunger mechanism above the top surface plate and use a chassis mount 10W resistor as the heating element for the DUT. The chip is placed on the top surface of the resistor insulated by polyamide tape, and thermistor is attached just above the DUT area with thermally conductive tape. This kinda worked OK for static temperature tests, but wasn't repeatable for sweeps, and we abandoned the concept. The main issue was the plunger prongs would conduct heat away from DUT and you needed to wait much too long for thermal equilibrium. We even tried to "cheat" by measuring the DUT temperature with a chip thermistor as the DUT, this is how we knew the DUT temperature relative to the heating resistor mounted thermistor, and fitting a polynomial to estimate the actual DUT temperature vs sweeps, but too much uncertainty for our liking, so idea was trashed. Steady state could work but would require very long wait time between temperature changes for acceptable repeatability, too long for our patience

Best,

[KungFuJosh]

In case anybody cares, the fan in the TH2830 isn't quiet. It's a lower pitch, but sounds about as loud as the fan in my SDS2504XP. I feel like getting quieter fans for both devices. I don't have a real dB meter yet, so I haven't tested actual levels.

[mawyatt]

If you feel the TH2830 fan is loud, don't consider a Hioki IM3536, it sounds like a jet engine

Best,

[KungFuJosh]

If you feel the TH2830 fan is loud, don't consider a Hioki IM3536, it sounds like a jet engine

Best,

That fan noise is part of it's $5000 charm, right? If it came with a $20 quiet fan, they'd have to charge an extra $1000. 😉

[Martin72]

Hm...AFAIK my hioki didn´t have a fan...

Tonghui/Sourcetronic:
Our ST2830 went back from external calibration, could upload the cal.-report(of course without names/adresses) when it´s interesting.

[mawyatt]

If you feel the TH2830 fan is loud, don't consider a Hioki IM3536, it sounds like a jet engine

Best,

That fan noise is part of it's $5000 charm, right? If it came with a $20 quiet fan, they'd have to charge an extra $1000. 😉

This is normal too!! You would think at that price point Hioki would have "paid" more attention to the fan noise 

Can you imagine if Siglent or Rigol had something this expensive with that level of fan noise, "fan" boys and girls would have a field day with them!!

However it is 80 times higher frequency (8MHz vs 100KHz) than the TH2830, so guess they needed to use some higher power consumption components (probably expensive too) and thus the higher thru-put fan, and a much more difficult design task!!

Anyway, not happy about the Hioki fan noise, but otherwise it's a superb performer. It's earned it's keep, because when we needed those higher frequency measurements, they needed to be spot on and the Hioki delivered

Note: "Puns" intended 

Best,

[KE5FX]

I've been really happy with my TH2811D.  No fan, and it offers a few different test frequencies and voltages.  At $400-$500 it satisfies the $500 budget constraint.  Might be worth considering if you don't actually need to do everything the TH2830 will do.

Edit: nvm, I see your search ended successfully. 

[KungFuJosh]

I don't need this right now, but I'm curious. How much do you guys pay for your external calibration? What's normal for that?

[KungFuJosh]

A sound meter app on my phone, with the phone about 6 inches away from the TH2830:

Room noise average: 45dB
Average with TH2830 powered on: 57dB

[KungFuJosh]

What mains fuses do you have in your TH2830 using 120VAC? It occurred to me I probably need to change it since this was setup for 220V.

Thanks,
Josh

[pope]

What mains fuses do you have in your TH2830 using 120VAC? It occurred to me I probably need to change it since this was setup for 220V.

Thanks,
Josh

Assuming the fuse value is correct for the 220VAC, I would use a 2x this value for 120vac.