12 Circuit Fuse Block W/Negative Bus - JOYHO ATC/ATO 12-Way Fuse Box with Ground, with Negative Bus & Protection Cover, Bolt Connect Terminals, 70 pcs Stick Label, for Vehicle Car Boat Marine Auto

When I troubleshot this unit I made an incorrect assumption I thought that I had a fault when the fault was with me I used a defective fuse, after further troubleshooting I found my error. I found that all my earlier statements were wrong.Don't let the fact that there is a negative buss bar confuse you. I am sorry for any wrong statements that I made

Many on Amazon have an LED indicator light and everyone complained in the reviews that they passed power even without a fuse. So, I went with this one. It works as it should. No fuse - no power, fuse - power. Who'd have thought?It seems to be very well built. It installed easy. The negative side is bussed together so that made install super easy. Screws and terminal seem solid. No complaints.

The fuse does not complete the circuit across adjoining screw terminals. Instead the large + terminal is bused to one side of the fuse block and the fuse completes the circuit to the positive screw terminals. This is not standard or intuitively designed. I had to disassemble the block to discover this. Additionally, the bus bars and terminal bases are very close to each other and are not properly isolated to prevent risk of short circuiting. I machined away metal in areas of potential contact to reduce the risk. Finally the negative side is pointless. It could just as easily be accomplished with the single large terminal. There is no value in the row of screw terminals on the negative side. Once the strange design is understood, it is possible to adapt to it - but it will not work for more than one power input.

Product appears to be high quality on visual inspection. However noticed fuses are hard to install as the clips are very tight and actually score the fuse blades when installing and removing. Also when connected to power i noticed an arcing internally. Removed all the wiring and pulled the back panel off and found that the negative bus bar and the fused outlet terminal were so close to touching right out of the box that it made an electrical short when a fuse was installed. This was only for one fuse location. I removed. All the parts and trimmed the bus bar and the terminal to increase clearance. I no longer have any concerns about it functioning but the design wasnt exactly the best. It will work as intended now that it has been modified.

The manufacturing on the unit is reasonably decent. The plastic is nice and the screws and metal bits are OK. The included dome nuts are plastic (probably nylon) which is good because the screws that hold the clear shield on are live.The problem is the awkward overall design/implementation. The screws that hold the clear shield on are live, which is understandable but kind of uncomfortable.The positive and negative coming out opposite sides is understandable, but kinda makes the thing unwieldy unless you have an unusual arrangement.The internals of the device are the most troublesome. As another reviewer mentioned, the metal bits on the inside are not separated enough. Like the negative bus is kind of too close to the positive ends, and there's no physical separator between them. Including the fuse contactors. They're all just kind of expected to behave nicely and not move around.They could have easily molded some sort of physical separator into the housing itself, but... they just didn't.So it's overall kind of an awkward design/implementation. Not a bad idea, but not anything I would actually use in any of my projects.

Yes the grounds are connected to the main ground lug on the one end. How else would it work? Main power attaches to other end. I used it to power my instrument cluster, lights and coil. Basically its 6 inline fuses in a handy block with mounting screws. I did put an inline 30amp fuse on main power in just in case. Its basically a fuse box.

The cover on this unit sticks up much higher than I wanted, so I thought to cut off the high center "hump" and glue a flat piece of plastic over the hole. This was much tougher than I expected. I spent half an hour trying to cut through the cover with various hacksaws before I gave up and used a rotary tool with a cutting wheel. The cover is made of some really tough material. You don't need to worry that it will break.I really like that compact design and that you can install fuses and that it has indicator LEDs to show when a fuse is blown.

Electronically it seems well made (though I'm no expert). It seems sturdy enough in both the metal and plastic parts.Frosted cover with plastic nuts was nice, making good out of the middle of a wiry clump. I kind of wish the + & - terminals were more in line with the other outgoing wires, to reduce the wiry spread, but no biggie--there's probably a reason for it. Comes with labels, some that one can customize for the different fuses, with say, a silver Sharpie.