cw-80 transformer problem

Probably blew the internal inline fuse---can be replaced---

Yup. Sounds like the internal 8 amp fuse blew. What accessory are you running? Is it supposed to draw more than 8 amps? If not, you have a short circuit somewhere.

Gerald,

    IMO the CW-80 is not a transformer worth fixing, purchase a bigger better transformer, I suggest a Z-1000 as a minimum quality transformer to all the guys I help get started.  If you plan to expand, an old KW or ZW with Scott 10 Amp breakers works great, especially with the DCS.

PCRR/Dave

 

The transformer is actually a spear,the accessary operates on 12 to 18 volts ,i will try to get it apart & see if i can fix it,if i can't then i will just get rid of it & get a kw for a spare, i allready have one kw,2 cw-80's,2 type r 110 watts.

I did manage to get the cover off the transformer & i do not see anything that looks like a fuse,i didn't even see the fan thats suppose to be in there any suggestions as to what i should be looking for?,like i said,i do not know much about these things,but i would like to learn.

The fan is enclosed in the top portion if the case. The fuse is in one of the wires that goes from the transformer to the circuit board in the top portion of the case. The fuse may be covered in shrink wrap so its not obviously seen.

If there's no fan, then it's a version of the PowerMax, not a CW.

Flash,you were right on the fuse was covered with some kind of shrink wrap,however it looked ok to me there were no burn marks the wire in the fuse looked solid to me & as far as the fan goes i did not look any further, i was just curious as to where it was. I pluged the transformer in i can here a humming noise, but still no power, it looks like this transformer is headed to the scrap pile,unless there is another option available but thanks for your help.

The best way to check a fuse is with a multimeter. Can you post pictures of your transformer while you have it apart?

Flash,i just put it all  back together the fuse was sodered on both ends,i have a meter from radio shack that i use to check the voltage on the tracks if thats what you mean by multimeter ,also where could i buy a fuse if i had to replace it ? I could take it apart again it was not hard to do,i will see tomorrow if i have time i'm not sure if i can post a picture but i will give it a try.

Set your multimeter to ohms (resistance) and put the leads at opposite ends of the fuse. You should probably get a reading of 1-10 ohms which is good. I don't know what humming you hear but if its the fan it should be obvious. Also, if the fan IS working then the fuse is good. Seriously, post a picture of this thing. It makes things a lot easier to understand.

I have the transformer apart,i am waiting for the battery on my camera to charge up as soon as this happens i will try & post some pictures,it's been awhile since i have done this so bear with me i should be able to do this sometime today.

The fan is attached to the back side of the aluminum piece where the 6 big holes are located.  See if it is spinning.

Dale,i see where the fan is so what i did was i pluged the transformer in & the fan was not turning,i then took a piece of wire & i by-passed the fuse , then i pluged the trans in & it came back to life,so it is the fuse that is blown,now the next question is where do i get another fuse?,lionel or someplace else ,any suggestions?  Thanks Dale & everyone for your help.

Question about fuses the one i need has 8a250v stamped on it ,i assume this means 8 amps 250 volts, i found one that is 1/4 inch longer,would that make any difference?,it still will fit in the transformer.

Having never taken the CW-80 apart, what kind of fuse does it have?  Is it a traditional glass fuse or something special?

 

Oops, I see you just posted.

 

Gunrunner John, it is a glass fuse when i do get one i will have to soder it back on,i hope this isn't to hard to do.I will try radio shack first if they don't have one i will have to try one of the online stores.

http://www.radioshack.com/prod...nt_content=CT2032234

How long is the fuse?  They come in all sizes, I see RS has the 1 1/4" ones and the 20mm ones on that page linked.

The one radio shack has is about 1/4" longer,does it make any difference it still will fit the xtra length isn't a problem.

I'd probably consider using the proper length, but as far as function, it doesn't make any difference.

 

Here's a page with a listing of the sizes of common glass fuses.

 

http://www.cooperindustries.co...s/Glass_Ceramic.html

Gunrunnerjohn;  does it matter which one i use,fast acting or slow blow type,i don't know which one the original one is.     Thanks for all your help i really appreciate it.

David,a great idea it would make things much easier next time around ,thanks for your help.

Gerald,

To answer your question about Slow Blow vs. Fast Blow.  A slow blow, at 8amps will "hang" for a few seconds at above 8 amps to compensate for a high "current in-rush", meaning it will tolerate a momentary current above the fuses' listed amp rating.  These are mostly used for motor applications.  At the instant of start of a motor it will draw more amps until it has come up to speed, dependent on its inertial loading.

A fast blow will see its listed amp rating and blow at that rating regardless of the transient climb above rated/listed amps.  Typically transformers and their current limiting fuse are designed to operate at 100% of their rated capacity, with 115% load to fail.  Because the fuse holder that I spec'd has long leads, you should be able to find someplace in the transformer to tuck it.

In short, I would use a slow blow in the transformer and a fast blow on your external "A' terminal, in series with your accessorie's connection.

 

David

Well today i went down to radio shack to get the parts i needed & of course they didn't have any in the store so i just went home & ordered them from radio shack on their web site this was the easiest way for me.I really wanted to do this not so much to save this transformer, but more to get some experience making my own repairs thanks to all the help from all those who responded i will reach that goal.There is allways a great feeling of satisfaction when you fix something yourself,instead of depending on someone else i will post when i finish this project, again my thanks to all who shared their knowledge with me.

Gerald,

   Good luck with your project.

PCRR/Dave

I rarely visit Radio Shack for parts anymore, they seldom have what I need.  My most popular place to go is Digikey, followed closely by Mouser.  Both have excellent prices.  Mouser has slightly better prices, but Digikey has dirt cheap shipping for small orders. 

Oh that reminds me. I should stop by SkyCraft while I'm in Orlando this week. If you have never been to the place, SkyCraft is a surplus store that is an electronics haven. The place is amazing!

Thanks for the tip, I'll look into that.

If you specify first class package, small orders are only a couple of bucks shipping, it's great when you just need a couple of parts.

That's good to know John. We use them here at work for small lot specials, but purchasing always gripes about the shipping. Then again, they always pile up things to get a box full too.

I can't imagine why shipping is an issue with Digikey, for first class packages, they charge actual shipping cost.  If you have a larger order, the price goes up.  If you pick some other shipper, the price goes up as well.

Today i received the parts from radio shack,fuse,fuse holder. The wire on the fuse holder was a heavy gauge not sure what gauge it was but i suppose it was for use in an automobile,anyway i put the fuse in,then i twisted the wires together & used a wire nut to connect wires,i then put the transformer back together & plugged it in,it starts up just fine,so i'm thinking everything is ok until i checked the voltage from the acessary side it reads 14.4 volts,still ok,next i checked the voltage on the track side 1.4 even with the throttle wide open,so i opened up the transformer to see if i broke a wire i don't see anything broken did i damage the electronic board somehow?,i have no clue as to what i should do next,any ideas besides junking the transformer?

I just went down the basement & for reasons i a'm not sure of i decided to reverse the wires on the fuse holder & when i checked the voltage on the track side of the transformer i am now getting 11 volts,i do not know why reversing the wires on the fuse holder made any difference but it did work,now i am having a hard time getting the cover on the transformer back on because of the size of the fuse holder,so i will have to make the wires a little longer so i can tuck the fuse hholder back inside.

Is it even possible to measure voltage output voltage without a load?

 

And even then, how do inexpensive volt meters do with the chopped waveform?

 

  --Joe

As Joe hinted, connect a light bulb across the output before making any voltage measurements.  Without a load you can get false readings.

how big of a fuse holder did you get? I'd got one from advance autoparts..its the one you twist on and off 1/4 of a turn.had no proublem putting my transformer cover back on..