DE-5000 LCR Meter - Power connector, Plug, Pin Information

[t1d]

I did not want to buy yet another OEM wall wart, for my DE-5000; I wanted to repurpose one. But, the DE-5000 uses an odd power input pin size. I determined that it is 1.35mm x 3.5mm (at least that worked for me.) I could not find such a ready-made connector plug, so I made my own, from a bare pin. P/N 490-PPM-2-35135-S1 at Mousey. HTH.
https://www.mouser.com/ProductDetail/CUI-Devices/PPM-2-35135-S1?qs=%252BEew9%252B0nqrAJtLwhjywFBw%3D%3D

[gdr771]

Yes, it's an odd one, thanks for the part number!.  I had to rob a connector from a different wall wart to splice onto a 9V unit.  Before connecting to the other wall wart I used the connector to power the meter from my bench supply, but it's very flaky and doesn't quite have the depth needed.   On the bright side I was able to measure the power draw: it's 10.4 mA at 9.00 Vdc and anything other than 100 kHz, in which case the draw is 12.8 mA.  With the meter turned off the parasitic draw is a steady 92 uA. 

Do you know the input power tolerance or the actual measured voltage output of the DER-EE branded wall wart?  The actual output of my 3 cheap 9 Vdc wall-warts are all above 11.5 Vdc at the measured current draw of the meter, so I don't want to plug one in unless I believe it won't blow up the meter.

Until then, I just installed a small toggle switch at the back next to the battery compartment to stop the parasitic battery drain.

[t1d]

Yes, it's an odd one, thanks for the part number!.

You are very welcome.

I had to rob a connector from a different wall wart to splice onto a 9V unit.  Before connecting to the other wall wart I used the connector to power the meter from my bench supply, but it's very flaky and doesn't quite have the depth needed.   On the bright side I was able to measure the power draw: it's 10.4 mA at 9.00 Vdc and anything other than 100 kHz, in which case the draw is 12.8 mA.  With the meter turned off the parasitic draw is a steady 92 uA.

Good information.

Do you know the input power tolerance or the actual measured voltage output of the DER-EE branded wall wart?  The actual output of my 3 cheap 9 Vdc wall-warts are all above 11.5 Vdc at the measured current draw of the meter, so I don't want to plug one in unless I believe it won't blow up the meter.

No, I do not know the DER-EE wart specifications. But, I built up my own DIY supply. I used a transformer-based 12VDC wart and a LM7809. It has at least 1A of output current, IIRC. That's plenty. You need to be careful with your selection of the wart. Firstly, a transformer-based unit is going to have much less electrical noise than a switch-mode type. And, two, you want to make sure that its output is actually regulated. Lots of warts do not include regulators and just allow the voltage to droop to the rated voltage, when loaded to the specified amperage. These warts are terrible and dangerous when used with other non-tolerant equipment. Additionally, lots of folks don't know that you need to add a full 3V of headroom, for a LM78xx-style regulator, to allow the regulator to reach its best ripple rejection. It's not just the 1.5V dropout voltage.

Until then, I just installed a small toggle switch at the back next to the battery compartment to stop the parasitic battery drain.

Good idea.

[Road Warrior]

I use this with great success:

https://www.amazon.com/Farsense-Adapter-Converter-Supports-Indicator/dp/B09NSHL19Q/ref=sr_1_10?crid=AX3WYG12Y3R3&keywords=dc%2B5-volt%2Busb%2Bto%2B9-volt%2Band%2B12-volt%2Bstep-up%2Bconverter&qid=1705264331&sprefix=5%2Bvolt%2Bto%2B9%2Bvolt%2Busb%2Caps%2C129&sr=8-10&th=1

[armandine2]

see attached

[5U4GB]

I use this with great success:

Interesting, thanks!  Have you run into any of the possible problems @t1d mentioned in terms of switching noise?  The photo of the bare-bones circuit implies it's not going to have the cleanest output.

Or any chance of posting a scope trace of what it's outputting?

For people looking for more of this kind of thing, your favourite crapvendor has vast numbers of these, be interesting to get a few samples and see what the output is like.  This one gives tech specs, can anyone translate the important stuff like regulation, ripple/noise, etc?