5 amp dimmer problem

I have a 4 X 5amp dimmer problem which had no light output. when i stripped the dimmer i found two of the fuses on the pack were blown. the fuse appears to be a ceramic sand filled fuse 1.6 amp similar to the fuses used in lighting packs for theater which are 10 amp. anyone know what would cause these fuses to blow. where can i get replacement fuses as these are solder in fuses.

 

If you're in Australia, Jaycar, RS Components, and Farnell should all have what you need, in other countries, most reputable electronic components dealers should stock ceramic slow-blo fuses.
Just get a standard one and solder it in. It is very rare to see ones specifically designed for soldering, and there is no harm in using a normal one intended for a fuse holder, and simply soldering the ends of it.

 

bassboz

thanks darpa i am in ireland. i am more concerned as to why fuse blew as they are not the most accesible.

 

I'm not familiar with the unit you're talking about, although if it is a 1.6A fuse, I seriously doubt it would be for anything to do with the triacs/loads themselves.
Sounds like (to my uneducated self) they are either protection for the power supply to the controlling electronics, or between the power supply and the controlling electronics.

It could be anything from dust building up inside+moisture in the air, a bug (insect), or something else conductive getting inside the unit and causing a short, or it could be that your unit is damaged or faulty.

Although I'm not familiar with the internal circuitry of the unit you're troubleshooting, it sounds rather suspicious that the fuse you're talking about would blow, so I'd definately be checking the board carefully under a good light, checking for things like dust, fried bugs (or bug-shaped marks on the PCB tracks where they may have been fried and then fallen out), and also pay careful attention for any black marks from shorts, or resistors that have begun to turn brown from overheating, or anything else that doesn't look like it's in pristine condition.

If you cant find any of the above, then there is likely a fault with the control circuitry or the unit, and it would pay to return it to clipsal for repair. Although I think you'd need to pay for that as opening it up the way you have would almost definately void any warranty it might have had.

If thats not an option for you, then you could POSSIBLY... take it to an electronics repair place and get them to check it out for you.

You can take the risk of simply replacing the fuses and pray that fixes it, however if there is a serious fault in the unit, doing so could cause more extensive damage to the unit, and it really could go bang in a big way, so unless you have balls of steel, I wouldn't recommend it until you've found the fault and repaired it. However, if you really really want to go this route, I'd first install something like a 1 amp fast-blo glass fuse, so that if something is seriously wrong, the fuse will blow much more quickly, and HOPEFULLY do less damage to the board. If you're confident that you've repaired the fault and testing the 1A fast-blo fuses shows up all ok, I'd then go ahead and install replacement 1.6A slow-blo ceramic fuses again.


Hope this helps you figure out your next step,
Darpa

 

5 amp dimmer

Hi Darpa,
there is no obvious indication of any external cause for fault . only two of the four fuses blew, leaving me without those two channels. There may have been a power outage or brown out as the residence is unoccupied. I was hoping that someone would be familar enough with the unit to be able to tell me the function of thew fuses in the circuits. Obviously the fuse is not protecting the output as the value is too low but the fuse must be expected to be passing a steady amount of the rated load or that particular fuse would not be used. I will try a fast blow fuse replacement and see what happens. My main issue is that I do not want to replace fuses have unit working reassamble , reinstall and then find fuse blows againe within a day or two

 

5 amp dimmer

Hi Nick. You are probably correct. This is an install which was finished nearly three years ago and has only been run occasionly for showing house to clients etc. The house has been repainted and extra finishing work done which means that the lights in question may have been on all day for a number of days. One light is a central chandelier which is drawing about 3 amps on full load but the other three channels are providing power for strips of agabekov lighting. I do not have the load requirerments for the aga bekov to hand but they are transformer powered and draw considerable current. Do you think that the transformers may be the issue or did I not calculate the loads correctly becaue of the transformers?
thanks
bassboz

 

5 amp dimmer

Hi Nick I am not sure that the transformers were supplie dwith the lights or if the electrician used his own , the closest traffo is nearly 15 feet in the air buried into an oak beam lovlely
will let you know how i got on thanks