domiflichi: @Runaway Pancake - Is it pretty standard for the 'ribbed' lead to always be Neutral on power cords in the US? (I never noticed that)
Ok, so a couple of you mentioned using a fuse before the input...so somewhere before the AC input basically. What's the best/cleanest/safest way of doing that?
The Best way to find out is with an ohmmeter.
domiflichi:
Ok, so a couple of you mentioned using a fuse before the input...so somewhere before the AC input basically. What's the best/cleanest/safest way of doing that?
I mentioned the use of an IEC receptacle, one with a fuse box.
Your supply may have its own on-board fuse, but nothing on the other side will.
If I'd stated, "Screw it, there's a breaker in the power panel" or similar then someone would argue with that, too.
Ok, so for those who are seeing blue where the green is, in my newest photo that I just attached, what color is the PCB? Lol
Hooray, there's a fuse inside! Sorry for the misunderstanding, I thought you guys were talking about some kind of external fuse.
Question - what is the white gooey stuff next to the giant capacitors? You can't see from the attached photo, but there's a lot more between those 2 giant capacitors, at the base of them. I'm curious what it is and what's the purpose...
Thanks again everyone!
(P.S. - I'm still not receiving 'update/new reply' notification emails)
The white gooey rubbery stuff is to secure heavy items, like tall capacitors.
Vibration, e.g. during transport, could stress the solder connections.
Sometimes I think applying it is done by blind people.
Leo..
Hi,
Did you by that powersupply as a new or used supply?
I use and repair if economical these MeanWell supplies.
They DONOT let units out for sale in that physical condition, the PCB should be sparkling clean, that unit has marks and liquid stains all over it.
The heatsink compound on the MOSFET in top of the picture has very sloppy application of heatsink compound.
That is not how they come out of the factory.
I'd say it has been reworked, that is a faulty or failed unit repaired, sloppy job because 9 times out of 10 these small supplies are cheaper to replace than repair.
Sorry to disagree Tom, but yes, that is how MANY of them come out of the factory. I use these and cheaper Asian supplies daily in production, and the condition of some of them is atrocious! However, they do usually work. Occasionally we will get a batch where all the potting compound to hold down heatsinks, caps, etc is broken away from the board in shipping mainly because the boards have so much flux residue (liquid staining) on them when it was applied. Other issues include loose hardware, poor solder connections (particularly on tabs riveted to the aluminum heatsinks to anchor them, and power components), and traces that have been lifted by over heat or mechanical stress. IMHO, every one of these supplies should have the board removed (if necessary for access), inspected under magnification, and possibly reworked before it is installed in anything intended to be at all reliable. Although they may work fine on initial installation, if they have not been inspected for problems, they may not work very long.
That said, Mean Well is in the upper crust of what I have seen. Now, if you are talking about open frame medical grade supplies, that is different. They are typically clean and some care is taken in soldering, post production cleaning, and mounting. GP supplies, not so much.
Basically there are three types of white stuff (or any color) used on these. Silcone, heatsink grease, and potting or thermal compound. The latter sets hard and often is used to hold on heatsinks to ICs. Rubbery....silicone, greasy...heatsink compound. Gray rubber pads under power components are heatsink pads that take the place of heatsink grease and usually offer electrical isolation as well as thermal bonding.
I looked at OP's pictures, and it's not a MeanWell-unit. It's the cheapest China kan make! - I would not put this into service before having looked closely over all solder joints etc.
