CR400AF - Interior light overloading the power pack - SOLVED

[Lessigen]

Earlier this week I received a package from Jacky at CNRailModel for a CR400AF-2006 with interior lighting. Looks amazing but I am having some teething issues with what I believe to be is the interior lighting overloading the power pack and causing it to trip the breaker. Would the play in this case to upgrade the power adapter from the one provided on a Power Pack SX to something like a 22-082?

 

 

Edit: Solution was the LED switch setting being set between the two toggles causes the LED to output way beyond its spec. See 

 

Edited Saturday at 06:37 PM by Lessigen

[disturbman]

Usually, people asking for help are having issues with the couplers. The interior light triggering the power pack breaker is a new one and that shouldn't be happening. Most Chinese modelers use Kato tracks and power packs to run their trains.

Can you describe better what happens? The train seems to be able to be powered and run on your pictures, meaning it's not a constant issue.

[Lessigen]

Sure! I currently have a large loop with a siding that I was intending to run with the full 8 cars. On the first proper run at half/mid throttle (enough to stop the lights from flickering), it'll complete about a full circuit, then the breaker will trip. I noticed the power pack got warm and started smelling like magic smoke after trying a couple times so I immediately stopped after noticing it and let it cool down. After some further testing of reducing the consist length from 8 to 6, then 5 then 4, I noticed it tends to overheat slower or I can run it at a higher speed before the breaker trips.

[disturbman]

Sounds to me that you should be testing all wagons and light units independently, preferable with a multimeter to see what draws what. It would give a clearer view of what is going on. As far as we know, the issue could also be with the motorcar or one of the directional light units.

Are these interior lights the ones that were factory-fitted or the aftermarket options?

[Yavianice]

What's most likely the issue is that the contacts in one of the trains are short circuiting. Check each car to make sure that copper parts are not short circuiting, the train is properly on the track, and that the wheels are properly isolated (I once bought a minitrix set that had a non-isolated wheel from the factory.... probably just a yuro thing, but doesn't hurt to check). 

[Lessigen]

Thanks to both of you for your insight.

 

@disturbman I did try testing all of the wagons, though I haven't tested the light units individually because I'm not really sure how to do that. My observations were as follows:

• Each of the units individually worked at full throttle with no shorting or warming of the power pack
• The motor unit worked as well at full throttle without any shorting
• I was able to test 6 units together in a non-moving formation, adding a 7th unit or more causes it to short at a higher level throttle (maybe 3/4). The 7th unit can be any car: an end car, the motor car, etc. However when these 6 units move they eventually short in roughly the same distance as a full consist.

I did not test with a multimeter as the cheapo one I have right now is only rated for 400 mA, which I believe if I try to hook it up it would blow the fuse as the power pack outputs up to 1.5 A. So I'll probably get a better one later. That said, I am not sure where I would start in terms of testing with a multimeter. I read online that you would set it up in series with the power pack and the track. Is that correct?

 

@Yavianice I ran a continuity test between the wheel pickups on one side of each bogie and they all indicated they had resistance so I don't believe they're short circuiting. I used the re-railer that Kato and TOMIX provide to make sure they're on the track and I didn't hear any of the signature "clacking" of a derailed unit as it went around the layout. Regarding wheel isolation, it looks like they are isolated correctly. I uploaded some pictures of the wheel pickups.

 

[cteno4]

That is an odd one. The best test now will be to get a better multimeter that will do like 2A and put the mutilmeter in line with one side of the power feed to see the amps drawn by each car.

 

did you try with a different power pack?

 

jeff

[Lessigen]

I was actually thinking about trying that next as well. I have a TOMIX N-600 that's rated for 12V1A which is less than the Power Pack SX but we'll see!

 

As for the multimeter, it'll be one of my next purchases. Gotta do research on which one is the best price/perf here in my part of Canada. I heard Kleins are good but they are pretty expensive outside of sales.

[cteno4]

You dont need an expensive one for this, just one thats a bit more beefie.

 

amp and volt meter wont work with he pwm which i believe the ss uses.

 

jeff

[Lessigen]

Thanks, I deliberated it a bit and got a decently cheap one that does 10A and is ETL/UL listed. Should be getting it by the weekend hopefully.

 

Until then I'll try with the TOMIX pack and report back.

[disturbman]

Changming doesn't make all metals wheelsets. Even their freight cars use wheelsets with a plastic axle, so it wouldn't be the source of the issue.

I'm pretty sure that you have correctly identified the issue, that some (or all) the interior light units draw too much current leading to the short. The fact that a random assembly of cars short when you grow from 6 to 7 would imo indicate that.

My question about the origin of the light units still stands. If they were installed by Jacky, he could send you new ones. And if they were installed by CM, you would have the recourse of sending the train back to him so CM can look at these. Or try replacing them with aftermarket ones, might be cheaper than sending the train back.

Did you talk with him about the issue? Maybe he heard of other similarly affected trains, but personally I haven't.

[Lessigen]

@disturbman Sorry, I meant to include that in my original reply to you but I forgot. They were installed by Jacky and not factory-installed. I am in contact with him about this same issue and he suggested taking out the lights. He'll be sending me a video to do so tomorrow since I'm unsure how to do it myself.

 

As an aside, I did try it with my TOMIX N-600 12V1A power pack. Same issue with it as well. I'm not sure if I damaged something because now there's a hum when I ran the CR400AF back on the KATO Power Pack SX that I don't believe was there prior. Maybe it's just the PWM causing the motor hum. Any advice on how to mitigate the humming?

Edited April 29 by Lessigen

[cteno4]

I sort of doubt if the lighting boards are drawing too much current that it will harm your motor at all. More that it would hurt the power pack than the motor as that current is going thru the lighting circuits not the motor. The SX is both pwm and constant lighting, the n-600 is just 0-12v output, so that make make different motors sound different. 

 

With he same result on the n-600 it rules out the board just not being happy with constant lighting or pwm power as n-600 i think is just basic 0-12v.

 

You wont be able to easily use a regular multimeter to measure voltage or amperage on a PWM circuit, so you need to measure using the basic n-600 that i think is no constant lighting added and just plain 0-12v output. Be good to measure the current draw of each car at like 8v before you pull the lighting boards. Maybe if a couple are not drawing a lot of current you can compare the install to one that is drawing a high current and see if there is something different in the connections or wiring that might show a short. Could just be a flaw in the boards or their components causing the short and thus high current definitely true if all the cars show a high current draw.

 

jeff

[brill27mcb]

Jeff, I am not understanding your thinking. As far as I know, a multimeter will measure the average DC voltage of a PWM supply, and the average amperage drawn. It will not measure the very short, repeating maximums during each pulse, but the usual pulse frequencies are high enough that average readings can be made. In fact, the average voltage is what the DC motors respond to, since their response is much slower than the pulse frequencies and lengths.

 

Rich K.

[cteno4]

I had read depends a lot on the multimeter if and how it averages things and it can give odd readings. I had looked at this a while back when i was playing with some simple pwm power supplies. Just simpler to read it on the plain Jane transformer and take pwm and constant lighting out of the measurement. 

 

Your logic sounds very good to me and basically my thinking as well.

 

jeff

[disturbman]

9 hours ago, Lessigen said:

@disturbman Sorry, I meant to include that in my original reply to you but I forgot. They were installed by Jacky and not factory-installed. I am in contact with him about this same issue and he suggested taking out the lights. He'll be sending me a video to do so tomorrow since I'm unsure how to do it myself.

I think CM had published a video about how to open the train as well. Could be worth digging into their official WeChat channel, though that might be hard to dig out.

 

8 hours ago, cteno4 said:

Maybe if a couple are not drawing a lot of current you can compare the install to one that is drawing a high current and see if there is something different in the connections or wiring that might show a short. Could just be a flaw in the boards or their components causing the short and thus high current definitely true if all the cars show a high current draw.

That definitely would be my guess. Now the real problem would arise if they all are flawed. Could be a design issue, but then Jacky should have gotten over reports. Maybe a defective batch and Lessigen was extremely unlucky, but these were produced in small-ish quantities and I would then expect Jacky to have heard about it by now. Or noticed himself.

[cteno4]

Yeah it’s an odd one! My guess would be more just a bad batch of components or the wrong component was used [ie wrong value resistor or cap] for part of a batch, i would expect a design flaw would have been caught. Production testing [if any] may be just apply some power and see if it lights up and not measure current draw for flaws. But if it wa a batch big enough to have most or all of lessigen’s train bad then i would expect the installation company dealer would have noticed by now or maybe just surfacing here.

 

The components usually on a lighting board are usually really low power components so hard to see any of them allowing that much current through them without frying which could still leave a short, but would take out the lighting.

 

jeff

[Lessigen]

Today's update: Jacky sent me a video on how to remove the outer shell. I removed the interior lighting on the motor car and noticed an immediate improvement, in terms of how much throttle I could apply before a short. Additional removals of interior lighting modules increases that improvement. Taking off 3 or so means I can run it at full throttle with no shorting. That said however, I am still noticing my Power Pack SX warming up during use over less than 5 minutes, even with half throttle...

 

I'll parrot what I did using his instructional video here on the forum in case anyone wants to do so as well for any reason. For keyword/search purposes I'll put the following text: Changming CR400AF remove outer shell for interior lighting

 

On the ends of each car there is a metal lip with a small space that you can use for leverage. You can use a pair of small tweezers and gently lever upwards to expose the blue flooring for the seat. Do not put the tweezers in too far in this space as you may pop off the blue flooring as well. Once you see the blue flooring, slide the tweezers and continue gently levering upwards until all of the plastic clips have been released. Be careful to not pull it off horizontally as the coupler and door are one unit, as you can see.

 

Once you have the shell exposed, you can see the interior lighting board and the pickups circled in red. Take them off or put them on depending on what you want to do. To reinstall the shell, simply snap it back into place keeping in mind the door.

 

I ended up taking off 3 interior lighting boards (1 from motor car, and 2 from the regular passenger cars), which is currently what I'm testing with. So far it seems to have positive results in terms of the throttle situation but still having problems with the power pack warming up over only a little use.

 

Regarding the multimeter situation, I should be getting it tomorrow or Friday. I need to get some alligator clips/test leads which I'll be getting. After which I can test the lighting boards independently. I've also contacted Jacky with my findings.

Edited Thursday at 02:42 AM by Lessigen

[cteno4]

Cool, progress! 

 

It’s odd that the motor car without the lightboard is tripping the breaker. What happens with the n600? This is a bit concerning as a single motor should not cause an issue like this.

 

could you take a picture of both sides of the light board, just interested in what they did.

 

jeff

[Lessigen]

@cteno4 Here are a couple pictures of the lightboard

 

I received the digital 10A multimeter today but I wanted to confirm if my thinking is correct before I commit and screw up something. I took a picture of my current setup after I did some searching. The way I have it set up, to my understanding, is the multimeter in series with the circuit if it the power pack direction is set in reverse (the positive comes out through the red wire) and the alligator clip leads will provide power to the cars through the rail and return neutral back to the power pack. Is this the correct way to do it?

[cteno4]

Yes thats how you measure amperage, you have to have the multimeter in series with the power circuit for it to measure the current flowing thru. It will be interesting to see what the readings are for with and without lighting boards and for the motor car as well.

 

Wow that is a lot of LEDs! 18 big ones and it looks like 20 little ones? Are the switches to turn the different sets on and off or a low/high setting? Maybe set for all on and on a higher setting. Im assuming they are turning all these leds down a lot. If they were full at 20ma then the 18 would draw 360ma per lighting strip, but im assuming they are below 6ma each. If all those leds were on at 5ma max then they would draw 190ma at full power which would exceed he max amps of the controllers with 8 cars on the track and give you the result you have, even at 3ma and the motor you could be hitting the max. 

 

Do the lights get brighter as you turn up the throttle?

 

It also has some sort of coin cell in there, im guessing that is rather a super cap coin cell or a rechargable battery maybe for antiflicker. 

 

@disturbman do you know anything about these light boards?

 

Jeff

[Lessigen]

Yes, the lights do get brighter the more I turn up the throttle. About halfway on both power packs results in its full brightness.

 

I'll unfortunately have to wait until tomorrow to actually test the current, as it turns out the multimeter leads I got with the multimeter are really stubby and it's difficult to clip to them, so I'll go out and buy ones that have a bit longer tip to them so the clips can properly hold onto them.

[disturbman]

4 hours ago, cteno4 said:

@disturbman do you know anything about these light boards?

No. I just know they were made after Changming failed producing enough themselves. They look like others I have seen before that were made to illuminate the inside of CM passenger coaches. They have the same high number of LEDs.

@SwallowAngel was supposed to get some as well. But I don't think he has received them already.

[cteno4]

@disturbman Do the small side leds [or what appear to be leds} also light up? What do the switches do?

 

jeff

[disturbman]

Really not an expert on these as I have never ordered any. Been playing with the idea for a while, but haven't pushed that button yet.

As far as I know, the side ones also light up. They allow for a more diffuse lighting and avoid getting the "little suns are burning in the middle aisle" effect you often get in models. All pictures I have seen of models with this kind of lights looked always quite good. Better than what I'm used to.