LeCroy AP031 - Replacement Model

[2X]

Hello,
do you have to suggest me another quality Differential Probe likef the "AP031 - 700 V, 25 MHz High-Voltage Differential Probe (÷10, ÷100)". I can't find it nowhere to buy it... do you know if they sell a new model like this for replacement?

[Martin72]

Hi,

It´s only a rebranded product, lecroy do not manufacture such things.

This one should be nearly similar:

https://www.datatec.eu/pico-ta041-tastkoepfe-differenziell?sPartner=Google-Shopping&gclid=CjwKCAjw-7OlBhB8EiwAnoOEkw4Y8pNndBpR_pUAUmOqWupVy_15Xy6gcx1_TUoKVMkiMCg0tQYWFhoCliAQAvD_BwE

But there are many many more alternatives on the market.

[2X]

Do you know any good model from ΒΚ Precision?

[Martin72]

Hi,

To be honest, no - At work all our differential probes are from Testec and at home I´m using a cheap one from micsig.

[2X]

Thanks for the replies... I didn't knew this company "testec."... This model looks very versitile "TT-SI 7002"... Do you know If I can see a signal of 5V at scale of x20 without big distorsion? The main reason that I want the probe, is to measure the output voltage from the inverter circuit (of CCFL Lamps ~750Vrms) in old LCD motitors.

https://www.testec.de/en/products/product-categories/differrential-probes/

[Martin72]

Oh, a new model..nice.
5V shouldn´t be a problem, we use ours daily and measure such low level signals.

[alm]

It´s only a rebranded product, lecroy do not manufacture such things.

This particular one was rebranded (made by Sapphire I think), but Lecroy has been manufacturing their own high voltage differential probes for well over twenty years now. Like the ADP30x series or the current HVDP series.

Thanks for the replies... I didn't knew this company "testec."... This model looks very versitile "TT-SI 7002"... Do you know If I can see a signal of 5V at scale of x20 without big distorsion?

Can you describe what you are measuring? What does the normal mode signal look like (bandwidth, magnitude) and what does the common mode signal look like (bandwidth, magnitude)? I'm not sure if you need a high voltage differential probe if your normal mode signal is 5V p-p unless the common mode signal is large.

[2X]

The main reason that I want the probe, is to measure the output voltage from the inverter circuit (of CCFL Lamps ~750Vrms) in old LCD motitors.
Do you beleive lecroy is higher in quality than the testec?

https://www.teledynelecroy.com/probes/high-voltage-differential-probes

[Martin72]

Do you beleive lecroy is higher in quality than the testec?

Can´t believe it, we use our probes for all purposes without limitations( we´re manufacturing power inverter/converter up to 187kVA).

[2X]

Do you remember the model of your probe?
For 750Vrms I beleive this model will be for me but I don't if will measure for instance a 5V signal or I have to take one probe for 750Vrms(TT-SI 8010B) and one another for 5V(TT-SI 7005).
Many thanks again for your guidance.

[Martin72]

I got one of them at home, this here...
We have appx 10..12pcs and some higher testec models with more bandwith/higher voltage.

[2X]

Shines Quality... One more question... On probe characteristics I see "Max. Input Voltage Differential Mode" &" Max. Input Voltage Common Mode". What is the difference? As I understand "Max. Input Voltage Differential Mode" refered when we measure a load at his two leads (potential difference), but what mean with common mode?

[Martin72]

Hi,
Maybe this helps:

[Sighound36]

Sorry a shamless plug here, I have a new used Lecroy AP031 HDVP still in original box with cal certifiate. still make a sensible offer and it can be yours

https://www.eevblog.com/forum/buysellwanted/teledyne-lecroy-ap-031-hvdp/msg4877801/#msg4877801

Martin is correct Lecroy mooved on these units about 8 years ago

https://www.teledynelecroy.com/probes/high-voltage-differential-probes

[alm]

Do you beleive lecroy is higher in quality than the testec?

The CMRR (common mode rejection ratio) at high voltages will likely be better on the Lecroy probes (ADP30x or HVDP, not the rebadged one). See this post by someone who was a project manager on the Tektronix high voltage differential probe which was designed by the same person who designed the Lecroy ADP30x.

Whether that is important for your application is not clear from your description. Is there even a common signal to worry about? Do you need a differential probe to measure the CCFL output or could a passive high voltage probe like Testec TT-HV 150 / TT-HV 250 also do the job?

[2X]

Do you beleive lecroy is higher in quality than the testec?

The CMRR (common mode rejection ratio) at high voltages will likely be better on the Lecroy probes (ADP30x or HVDP, not the rebadged one). See this post by someone who was a project manager on the Tektronix high voltage differential probe which was designed by the same person who designed the Lecroy ADP30x.

Whether that is important for your application is not clear from your description. Is there even a common signal to worry about? Do you need a differential probe to measure the CCFL output or could a passive high voltage probe like Testec TT-HV 150 / TT-HV 250 also do the job?

The CCFL is connected on a transformer output of an inverter, so as I know I need an isolated ground or am I wrong.

[Martin72]

Hi,
Its better, no question.
On primary side it wouldn't be necessary.
(It's easy to remember, als long as you are on the same potential side.)