Good afternoon Team,
I'm happy to hop in on some discussion content in these forums! I'm running into an issue with a recent TCS WowSound (WOW101-Steam) install I completed on an older Rivarossi 2-8-8-2. First, I will say the sound options in this decoder are awesome. I was pleasntly surprised with the number of different built in options provided. Let me try and explain what's happening:
At super low speed steps (Say, Speed step 1-10) the locomotive CRAWLS without any issues, and I love it. No binding whatsoever, hesitation,etc. However when I approach any speed above step 10, the locomotive motor will stall intermittently, and the engine will become jerky. Let's say this occurs for speed steps (11-29). Around speed step 30, I can get it to smooth out for a little bit, but around speed step 40 the hesitation returns.
I can try to rule out some things here.
1) Binding - There are absolutely no binding issues with this locomotive. I previously ran on DC only, and had no issues at all. If I remove the decoder, and put leads directly on the motor, I can get it to run very smoothly at low voltage. There are no issues at higher voltages either. The motor is not the original Rivarossi motor: I upgraded to a can motor kit I purchased off of eBay.
2) Power Pickup - I've recently started a new layout build, and the track is brand new! I have several other locomotives that operate with no issue whatsoever. I've cleaned the wheels on the 2-8-8-2 several times, with no performance improvement. By the way, this version does not have pickups in the tender, it picks up power from both front sets of drivers. It may be worth noting: When the hesitation occurs in the motor, I do not lose sound or power. The headlight is still hardwired in, and it does not flicker or blink.
Has anyone ran into a similar issue? I've been at this for a few days, and I just can't seem to figure out why the locomotive is behaving this way. Any suggestions would be greatly appreciated.
Thanks in advance,
Ben
If this is an older Rivarossi loco - did you test the current draw on DC before installing the decoder? It could be exceeding the limit of the decoder when running at higher speeds.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I think Randy missed the can motor replacement. What motor did you replace it with? Some can motors have caps inside that could effect the BEMF in the decoder. I have several can motors that have the caps but I haven’t experienced any problems with them. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
Yes but random can motor off eBay does not automatically equal low current motor. Other than being just 3 pole, those old Rivarossi motors weren't horrible, the good old streamlined Hudson we had always ran nice and smooth, as did the old-timers (had Reno, Genoa, and Bowker). Best running locos we had back then. A can motor MIGHT be an improvment, but as I recall, the instruction sheets for most of those older Rivarossi locos listed a max current of .7 or .9 amps, within the decoder's limits. But they didn't say if that was max running current or max stall current or "smoke will come out of the wrong end of your steam loco" current.
I think the heat started at about 1 amp and smoke was at 1¼ amps. The open round frame Rivarossi was 1½ amp locked roter. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
Hi Ben.
It would be helpful if we could know which motor you installed - number of poles (three or more), type (irone core/coreless etc.).
This infomation could point out (or not) in which direction you should investigate further. If for example you installed coreless motor, then I would not be surprised that TCS WOW has problems with it. My TCS WOW (all versions) had problems with two different coreless motors - a small one in Trix Mikado, and larger one (7-pole Escap 16 mm). On the other hand, it controls superbly larger coreless motor that is installed in my Trix Big Boy in complete speed range.
The problems you reported were similar to what I observed with these two coreless motors. With iron core motors, I did not notice any problem using TCS WOW - motor control is perfect.
Another thing that might be a problem - did you check if there is any kind of capacitor installed somewhere between motor and decoder? Capacitor can be a problem for a decoder, so if it is there, I think it is better to remove it. I doubt this is the case here, but it is good to check.
To rule out either faulty decoder or decoder incompatibility with chosen motor, you could test locomotive with another decoder, for example ESU Lokpilot 4 (if you have it at hand). This decoder has excellent motor control, especially for "difficult cases", like e.g. three pole iron core motors with very strong cogging. Of course, CV's related to motor control must be adjusted for your motor, if factory settings are not satisfactory.
Also, you could test this TCS WOW with any other locomotive, just to rule out decoder is faulty (motor control section only).
Hrvoje
What about the power connection through the drawbar. Could it have an intermittent connection?>
Are you using speed tables, or just CVs 2-5-6 for speed? I had a situation where an engine ran oddly at certain speeds, turned out I had set it to use a speed curve and a couple of CVs were mis-set so the steps spiked up-and-down. If you have DecoderPro, you can see it graphed out (which is how I caught my error).
All,
Thanks for your suggestions. You all gave me a few good avenues to investigate for the past several days.
I learned from the seller that the motor is a good ole' fashioned Mabuchi 12v DC motor. I checked out the stall current, I measured a maximum of .85 amps, well within the specified current of this decoder (1.3 continous, 2.0 Peak).
I've cleaned wheels again, and also built a keep alive circuit. I also added pickups to the tender. The overall loco operation is much better, but I can't get by speed steps 20-30. I've manually adjusted CV's 2-5-6, to no luck in these speed steps. Maybe I need to play around more, or get into Decoder Pro.
The loco also just doesn't decelerate well (Even after adjusting deceleration rates with CV4), so I'm maybe starting to think I need to check out a different motor. Any thoughts on the above?
Sorry for the delay here, work has been getting the best of me lately, and leaving me little time to dig around in the evenings!
Ben,
a picture inside a locomotive showing motor and drivetrain together with motor dimensions would be helpful for any recommendation on new motor.
One question - did you try the locomotive with wheels up, with plain DC? Not just low voltage, but the whole range - because problem occurs in medium speed range. Also, did you check to run it on DC thru the whole speed range?
The problem can be caused by some mechanical issue that has an impact only at medium speed - e.g. some part is not balanced well, or has too much play in joint/bearing. Such issues sometimes emerge only at higher speeds, not at slow or maybe very fast speed. Such problems are often followed by vibrations and / or rattle or another unusual sounds.
Also, a motor itself can be faulty - when removed from loco and connected to DC, it should start from 0 to max without abrupt changes in sound, which indicates RPM increase, and then back to stop. You should also not feel any excessive vibrations.
Of course - a decoder can be also faulty, therefore it is the most easy way to check decoder to plug it in some other loco that behaves well. And vice versa, to plug in this "problem" loco another decoder. In this manner you can quickly determine it decoder is an issue, or not.
I have a Rivarossi Y6B with a Mabuchi 266 motor and a tender with a WOW 101 decoder that is normally behind my modified Rivarossi AC-9s. I plugged it onto my Y6B and without reprogramming it and the Y6B runs perfect.I do have the BEMF turned on for the dual Mabuchi 266 motors in my Cab Forwards and AC-9s. Actually the BEMF doesn’t have much effect on my steam locomotives with Mabuchi SF266 or Canon EN22 motors. There is a capacitor in the Mabuchi motors but removing it didn’t make any difference so I no longer remove the caps.If the BEMF is turned off in some of my decoders they do strange things. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
Mel,
Good info to know. I've seen a few other posts about the Mabuchi SF266. I just ordered a handful off of eBay, because why not? They're cheap enough. If I get around to it this weekend, I'll swap some decoders out on one of my locos and see if I can't find the root cause.
I did rule out one item here. The decoder is not faulty. I installed in another Proto 2K Y3 that I have, and the engine runs flawlessly. I will continue to search for my solution!
RR_Mel I have a Rivarossi Y6B with a Mabuchi 266 motor and a tender with a WOW 101 decoder that is normally behind my modified Rivarossi AC-9s. I plugged it onto my Y6B and without reprogramming it and the Y6B runs perfect.I do have the BEMF turned on for the dual Mabuchi 266 motors in my Cab Forwards and AC-9s. Actually the BEMF doesn’t have much effect on my steam locomotives with Mabuchi SF266 or Canon EN22 motors. There is a capacitor in the Mabuchi motors but removing it didn’t make any difference so I no longer remove the caps.If the BEMF is turned off in some of my decoders they do strange things. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
After several months, my Mabuchi 266 motors came in from across the ocean. The locomotive runs exceptionally well now. Root cause: Motor provided in the kit was not adequate. Thank you for your help and your patience. This is an exceptional group of people, with vast experiences to share within this community.