hi does any now if the std slb have a fuse that you can repair
Julian
in uk
Hi Julian,
IT seems it does. According to the open loop SLB schematics designated FUSE1 protecting for amps, not for slightly higher voltages. Does the board do anuything at all or is it dead in the water without green powerlight?
Since I donot own a standard SLB nor do I have access to better quality board picture, I cannot help l;ocate it for you other than show where I suspect it to be found. (blue square)
I don’t know if these are clear enough to help but I’m willing to take more if it will help. Just point me in the right direction.
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Eyyy Michael,
Oooh you have one. Zi don’t see a fuse like component in your pics. The ones I know are mostly white ceramic rectangles rather large in comparison to the resistors. A bit like the glass tube diode designated D1, almost visible bottom right in your third picture. Looking for the components R43, D21 and R125 to be near it. The component might just have F1 as designation.
Could you make a few pics of the board right section progressing to the left while keeping the whole width of the board in frame? It seems to be not located in my suspected area.
I think these are in order.
EDIT: I see a fuse1 in the first pic. It’s roughly in the center of the lower left quadrant. D21 is there as well. It has JG on the actual component, I think.
Just found R43 and R125. They are just above the white connector in the same area.
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Nice job Michael. When that fuse blowes, the power enable line is gone that is needed to start up the on board power supplys that power ics and stuff leaving the board blanck. Replacing that fuse might be not for all. There is an option to just short it with a gloob of solder, but that I leave to the one owning the board. It would not be my choise. At least not permanent. I might do if I need the board to work while the component ships.
I might also choose to wire in a glass fuse to bridge the time.
Anywho, nice detective work Michael. You rock.
Oh, if you do not have a measuring tool to check the fuse, you can rudimentary use a screw driver or metal someting to bridge the component to see if the board is activated. If not, you are in bigger trouble.
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Ummmmm … do we know why the fuse blew? It is exceedingly bad idea to short-circuit the fuse unless you precisely know the failure mode. Even if you say that ‘I just shorted two terminals together’, unless you have looked at the schematic and determined EXACTLY what would have happened during the short circuit, you may have other components that failed.
Going for a temporary glass fuse is an acceptable method of starting to trouble shoot. It is possible that everything still works but there is just as much of a possibility that other components have failed. If other components leaked out their magic smoke you could either have a dead board (still) or you could have an even deader board as more magic smoke is released.
I thought it was because he used a 36V power supply when the SLB is only rated for 24V max.
That seems reasonable (I forgot about the 24V bit) but if that is the case then short circuiting the fuse is a big fat hairy no-no with bells on, a generous helping of whipped cream and a sprinkle of cinnamon on top!
Actually, let me change that … go ahead, short circuit the fuse, you have nothing to loose. Chances are 99.99% that the board is toast (literally). Have a fire extinguisher handy!
Nownow jens, don’t be a scarecrow. As you said, the board is or isn’t toast. If it isn’t, shorting the fuse is okay, and will bring light and happy feelings. if it is toast, shorting the fuse will not toast it more. The damage has been done or it has not.
It’s schrodingers controller and the only way to be sure is through the fuse. You measure it and if you cannot, you short it. The 36 Volts has been introduced on other parts of the board already. The fuse does not kill the input power perse, only the input power to the 5V section and a check line for other voltages (3v3, 12v etc) to come life, if it has the correct vallue.
Power supplies can be pretty sturdy when offered a offset voltage not meant to be fed into the system. Since the original post hinted at the wrong supplied voltage, and I’m assuming the correct voltage (24V) is now going to be supplied after the mistake was recognised, shorting the fuse can not dammage more. Shit has happened or it has not. If it will bulch smoke the bad voltage cascaded as far as it could and the components doing the extra smoking while on the correct voltage were allready compromised and would have needed replacement anyhow. Theres nothing magical about that.
I would measure the fuse to see if it’s actually broken, wich I doubt. If it has blown, I would short it to see wich side of Schrodingers controller I am stuck with. Prolly a live one.
If I cannot measure the fuse, I would short it without second thought to be done guessing.
LOL … please video the fuse shortening. I’d love to see what the result is.
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Bridge the fuse with a light globe. If there is a major short somewhere, the globe will control the current flow.
If it’s just a blown fuse and there is no other damage due to the 36v, the board will, more than likely, turn on.