HP / Agilent 6621a “System Power Supply” as bench power supply for mobo repair? - Page 1
Forum section: electronics / beginners

author: mrpinkdonttip
author_rank: Newbie
timestamp: March 26, 2018, 06:28:22 am
content: Hi All. Thanks for being here. I run a computer repair & consulting business and am going to be trying to learn how to do component level repair on boards. I’ve been wanting to do this for years and finally got the gumption to, I’ve been doing a lot of reading and youtube video watching, I’m excited to be learning something completely overwhelming again. )I bought an hp 6621a power supply. I bought it because I thought it was like the one Louis Rossman has and recommend (guy on youtube with a alot of great tutorials/ info), thinking it was just a little newer but the same idea, based on the model number (his is a 6542a.) upon further reading they seem very different actually and am wondering if I screwed up and won’t be able to use it. The 6542a is called a “precision power supply,” the 6621a a “system power supply” the 6542a is 200 watts, 6621a is 80, the 6621a also looks to have other features (like it listens and adjusts voltages based on readings?) Can you guys please tell me if I can use the 6621a as a benchtop power supply for board troubleshooting? The manual is here:http://literature.cdn.keysight.com/litweb/pdf/5957-6377.pdfThank you!Ed

author: xani
author_rank: Frequent Contributor
timestamp: March 26, 2018, 03:39:00 pm
content: If you already bought it, why not, just it won't be as convenient as dedicated lab supply (connectors at the back being one inconvenience) and it seems to be pretty fucking huge compared to what it offers, especially if you don't need any of the programmability of it. Something like KORAD KA3305P will take much less bench space.

author: mrpinkdonttip
author_rank: Newbie
timestamp: March 26, 2018, 05:19:49 pm
content: Luckily the ebay seller hadn’t shipped it yet and is willing to cancel the order. I had chosen the hp cuz I agreed with louis’s logic about the older high end ones being a better value than the new cheap stuff, but I certainly don’t know much. Is the KA3305P a favorite here? I was trying to keep my cost under $100 (had got the hp for $90 shipped.) Thanks for the help.Ed

author: mrpinkdonttip
author_rank: Newbie
timestamp: March 26, 2018, 07:42:30 pm
content: I went ahead and bought a korad ka3305d, I found one open box for $150 and it seems to be a good one. I like also that it will apparently stay pretty quiet for my purposes. Thanks for the help!

author: xani
author_rank: Frequent Contributor
timestamp: March 26, 2018, 10:39:34 pm
content: There is this threadhttps://www.eevblog.com/forum/testgear/inside-the-new-korad-ka3305p-linear-psu/Dave has also reviewed on of their previous ones and it seems they improved upon the design.I had their previous one (which looked like 2 single power supplies stuck together) and had zero problems with it and it seems they made fan much quieterHere is comparision:https://www.youtube.com/watch?time_continue=1&v=WRZY9mYmFBk

author: ogden
author_rank: Super Contributor
timestamp: March 26, 2018, 11:10:06 pm
content: Particular system/rack supply is nice specimen indeed - they are built like a tank. You are fine with such supply as long as during your job you don't have to change supply voltages/current_limit often. You just have to 1) put supply where you can easily reach supply controls, but not necessarily on the table 2) manufacture remote terminals with remote sense. When you need to put many amps into the load, remote sense is handy - it ensures that voltage regulation is done where your load is, not at the supply terminals which can be many inches of (unknown resistance) wire, away.