review + teardown - Agilent U8001A 30V 3A linear power supply

[Spikee]

So i just filmed a short tear down of the Agilent U8001A.





Short review:

Very well build power supply from Agilent ! This is in their budget range so it does not have any lan / serial / GPIB connections.
I bought it for around 280 euro on Farnell and it got delivered within 24 hours. The noise from the fan is not to bad on the low / high settings.
It can handle shortcuts very well (as expected from a top brand) . It can also handle the 90 W continuous without any signs of getting hot. Even the exhaust fan is still pushing out cold air. Everything you expect from a good power supply.

Feedback:
The fan goes into high speed mode above 2 A. So if your load is pulsing you can hear the fan jumping from low to high setting.
It's quite a long and heavy power supply ( it can be a drawback for you) . The power supply is well build and there is a lot of quality control even for this budget model. There is also great attention to details like the copper clips that ensure for a good connection between the pieces of the metal case to make a good cage of Faraday .


Pictures:

Frontpanel:
http://dl.dropbox.com/u/100819959/Agilent%20U8001A/20121219_210903.jpg

Top view:
https://www.dropbox.com/s/gxryk8vsj5a0exf/20121219_210851.jpg

Input terminals:
https://www.dropbox.com/s/ad4pgdhyvv7lp92/20121219_210816.jpg

Caps + heatsink :
https://www.dropbox.com/s/addufkoh9s8i7iv/20121219_210649.jpg

Microprocessor / ADC (main chip) :
ADUC848
http://www.analog.com/en/processors-dsp/analog-microcontrollers/aduc848/products/product.html
https://www.dropbox.com/s/cfewtw1828jiyd0/20121219_210637.jpg

more info is in the video.

Rest of the pics:
https://www.dropbox.com/s/kdsmatevk8y22w6/20121219_210612.jpg
https://www.dropbox.com/s/glie3idrouy3ek2/20121219_210630.jpg
https://www.dropbox.com/s/ud09cdoxh6ni4gi/20121219_210645.jpg
https://www.dropbox.com/s/y1lw2hn4gf6qjf7/20121219_210658.jpg

Voltage regulators:
https://www.dropbox.com/s/4fys3sdof8z1lwl/20121219_210739.jpg

IRFP150N:
https://www.dropbox.com/s/dkgggv2abk4h7xs/20121219_210756.jpg

Input panel:
https://www.dropbox.com/s/r22gkhp47rijzvq/20121219_210828.jpg

Display lcd:
https://www.dropbox.com/s/3r320m5pgd2ak21/20121219_210834.jpg

Overview:
https://www.dropbox.com/s/3ndg30rudf23zh7/20121219_210847.jpg
https://www.dropbox.com/s/dsspo09gq6t87b2/20121219_210841.jpg

If their are any questions just contact me via YouTube / EEVblog or just post it here

Gr. Spikee

Edit:
Put the new youtube link in.

[Alex]

Hi Spikee,

Thank you for the nice pictures!

Just one question, do you know if this is Agilent's own design?

Alex

[Spikee]

I'm not completely sure but it seems that it is. I coulden't find another brand on the pcb.
See free_electron reply.

[free_electron]

Agilent design made by their Escort division. They absorbed Escort ( a taiwanese instrument maker ) about two years ago.

[Spikee]

The YouTube link is broken.

Just search for spikeguns1 on youtube an click on the last video.

[robrenz]

Nice review Spikee  are you going to do a performance review next?

[Spikee]

Nice review Spikee  are you going to do a performance review next?

What would you like to see ?
Noise performance , if it overshoots , put it on the dummy load , load regulation ,over current , over voltage ...


Please reply.

Gr.spikee

[robrenz]

Nice review Spikee  are you going to do a performance review next?

What would you like to see ?
Noise performance , if it overshoots , put it on the dummy load , load regulation ,over current , over voltage ...


Please reply.

Gr.spikee

If you have the time and desire, all of the above. It would also be nice to see how the control panel works

[anotherlin]

Nice teardown.

Do you have any idea why there is a second transformer (may be a choke instead) along with the (big) main toroidal transformer ?

[saturation]

Yes, second, very nice teardown and most excellent photos.  Performance test please!  As freee- said, you can see the made in Malaysia label on the lower right of the main mobo images.  The LCD panel and controls board have either made in Malaysia or Taiwan labels on them.  On the main mobo, top notch components all around, impeccable assembly. 

It looks like the small transformer is the PSU of the main board.  I'm guessing the entire control section is a complete module so all that needs changing is the toroidal and the firmware, to get to the next model up the line.

[anotherlin]

It looks like the small transformer is the PSU of the main board.  I'm guessing the entire control section is a complete module so all that needs changing is the toroidal and the firmware, to get to the next model up the line.

Spikee, sorry to bother you 
But you can easily check that guess and answer us.

[Monkeh]

The red wrapped core is a big damn inductor, not a transformer. There are only the two wires going in, and they're way too big to be for anything but the main output. The control supply is via the small white connector.

The grey wire running back to with the output wires is sense wiring (makes it easy to rig up remote sense if you want to).

If there's a relay it's probably tucked under that inductor.

[krish2487]

And in addition to what monkeh said,

(I am almost certain)
the white ic is an optocoupler to drive the mosfet next to it.

maybe a TLP250 or so..

[kek]

Just received a U8002U two days ago. Looks the same on the insides, main board marked "U8001-26001 Rev A"
... maybe a software mod to go from 3A to 5A?

Ken

[kek]

Just reviewed Spikee's video, looks like the main transformer is shorter than the one in the U8002A. Couldn't see what the main secondary winding was rated at but the U8002A is rated 36V 10.26A.

The data sheet shows the U8002A is heavier, copper is expensive if not needed I suppose.

[sotos]

I have the Agilent U8002A 30V/5A. I will sell it because I bought a programmable Tektronix PWS4305 power supply.
I think that I can open it and make some pictures, if there are no seals.

[saturation]

You're right Monkeh, I stand corrected  , but if someone can check that fairly large inductor to insure it is what it is.

The red wrapped core is a big damn inductor, not a transformer. There are only the two wires going in, and they're way too big to be for anything but the main output. The control supply is via the small white connector.

The grey wire running back to with the output wires is sense wiring (makes it easy to rig up remote sense if you want to).

If there's a relay it's probably tucked under that inductor.

[Monkeh]

I doubt it's an inductor it has a red and blk wire coming out going to the connections on the PCB labeled as 36VAC. [edit] Actually I bet it is a comon mode choke,it would make sense. You would need a high inductance to offer even 1k impeadance at 100 or 120Hz. With E-CORES if you have a split bobbin you can also benifit from significant inductance for differential filtering as well so its economical. Lots of layers multiple outputs so capacitance would start to add up so a CMC is probably a good idea.It's hard to say for sure without measuring or at least having a close look where the wires going in are coming from and where the traces go from the wires going out.

It is, indeed, a common mode choke. Which is just an application of an inductor.

[PA0PBZ]

It is, indeed, a common mode choke. Which is just an application of an inductor.

That’s why I had the edit about 5min after posting the light-bulb went-off.

A common mode choke should have 4 wires, not?

[Danstroem]

Hey guys,

just a short question: I ordered a U8002A 30V/5A with firmware "0549 0". Unfortunately, the fan is always on full speed, even when setting limits to 1V/0.1A. Any ideas, why it isn't slowed down? Very noisy

Any comments greatly appreciated!

Daniel

[Spikee]

I dont know about the 5A version , you could contact agilent ?

[Danstroem]

Unfortunately, the fan is always on full speed, even when setting limits to 1V/0.1A.

Correction: The fan did not run on full speed. As described earlier with the U8001, the fan switches between low and high speed at 2A load. I think, even the low speed is very annoying. The audio meter measured 51 dBA (1 meter distance) with U8002 on low fan speed. Too loud for me. I talked to the Agilent support. It is how it is 

[sotos]

Unfortunately, the fan is always on full speed, even when setting limits to 1V/0.1A.

Correction: The fan did not run on full speed. As described earlier with the U8001, the fan switches between low and high speed at 2A load. I think, even the low speed is very annoying. The audio meter measured 51 dBA (1 meter distance) with U8002 on low fan speed. Too loud for me. I talked to the Agilent support. It is how it is 

I friend of mine with same problem, changed the noisy fan with one of these.

http://www.blacknoise.com/en/site/page/products.industry

[sotos]

I also know that problem with fan noise. Although having a U8002A sitting around, deciding what to do with it, I think I will change the fan with one of this, it just costs 6 to 12 euro’s, for a super quiet.

[Huluvu]

Hi Sotos,

be carefull with the super quite Fan's
I think somethimes there is a need on the airpreasure too!

Therefore I would recommend to compare the Datasheets or keeping an extra Eye on the internal temperature distribution after changing the Fan

Rgds Arne