Reversing Circuit Miniatronics RU 2-1

[cteno4]

started a new thread on this guy as seems there are some folks interested and ill start posting my progress with the unit.

Just hooked it up this evening to test and it works great out of the box!

Basics:

Miniatronics RU 2-1 auto reverser with 5 stops

http://www.miniatronics.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=M&Product_Code=RU2-1&Category_Code=&Product_Count=0

I got mine from the engine tender for $79.95 plus like $6 shipping (list $99.95)

http://www.enginetender.com/475m.htm

• the unit has a 12vdc wall wart power supply that supplies the unit and track power (up to 2 amps).
• it comes with 7 sensors (2 reversing circuits and up to 5 stops). the unit has a sliding pot on it to control the speed of the train. this unit is great as you dont require a separate power pack to regulate the track power the way a lot of these reversing units do.
•  it also has break/momentum built in so that the power is not just shut off slamming the train to a hard stop (lots of the other reversing units just do a hard power on/off), but you get a fairly graceful stop and start
• you can set the pause time for each of the 2 reversing circuits and from 1 to 25 seconds individually and they are saved in a eprom.
• has short circuit protection with auto shut off

How It Works:

the RU 2-1 uses photo resistors that you mount between the rails where you want your trains to stop. when the train goes over the photo resistor the resistance goes up and triggers a stop or reverse (whatever circuit you have the sensor plugged into).

when the unit is powered up each sensor is polled and its resistance is measures and set as the trigger level. this means if the lighting level changes in the room the unit will reset itself to adjust for it. also means that if one sensor is under a bright light and the other is in a very shaded then each is set to the level it needs. this is a big advantage over a lot of other units some can be really cranky trying to set the sensitivity of each sensor manually with a pot on the main unit...

Reversing circuit - when a sensor plugged into these 2 circuits is triggered the train slows to a stop, waits your preset amount of time set for that circuit, then reverses track polarity and starts the train up again

Pause circuit - when a sensor plugged into any of the 5 pause circuit is tripped the train slows to a stop, waits your preset amount of time set for that circuit and starts the train up again

each circuit has a 6 second timeout so that once its tripped and goes through its routine its locked out of being tripped for 6 seconds so if you have a longer train and it did not clear the sensor its not tripped again right away before the train gets off the sensor.

the cool thing is you can have it ignore the reversing and just have it do stops. so if you have a train on a loop you can just have the train pause at up to 5 stops on the loop.

Uses:

Well tram lines seem the most obvious that are in a point to point set up, but any point to point train would be cool. also since you dont have to trigger reversing circuits for the unit to work you could do a loop that just stops at up to 5 stops, pauses and takes off again!

Im planning on using this on the ttrak modules and just put a sensor into each module that has an appropriate place to stop and wire the sensor wires with simple plugs. then whatever way i set up the modules i can just plug the sensors in from the modules i want to have stops at to the unit. the unit takes care of the automation and track power in one little box!

when storing modules at home i plan on putting them on long shelves on the wall of my office. with a module at each end plugged into the reversing circuit i can have a shelf of modules running in a point to point. we are also looking at running point to point set of modules along one side of the new jrm layout.

Pros:
• 2 reversing and 5 stop circuits
• simple sensors to install
• auto sensitivity setting for each circuit on powerup
• built in power supply/throttle
• momentum/brake feature
• auto overload/short circuit protection

Cons:

Not many so far. the momentum/brake function means that the train wont stop in exactly the same place on a stop sensor in each direction. with a slow moving tram this is only like a 0.5-1" difference, so no biggie. with a faster train it could be a few inches, but not sure the momentum/brake is slow enough to be good for faster trains.

ill take some pictures and video soon. i just hooked the sensors up to the unit and tripped them with my finger. next ill try mounting them in some track sections to play with.

cheers,

jeff

[Tenorikuma]

That's very cool, thanks for the information.

[disturbman]

Thanks Jeff, that seems interessant.

Subject moved in DCC and Electrical... Layout computer control/Automation.

[Bernard]

Jeff - Just a heads up. When I tested my RU1-1 there was a problem. I called up Miniatronics and the rep told me to switch the wires on the supplied transformer. It seems like one of the guys in the back, put all the (+) positive labels on the wrong wire before they found the mistake and shipped out a whole bunch of units.

[cteno4]

Thats a bummer!

all worked fine on mine and i checked the polarity and its correct as labeled. joes works fine except one of the reversing circuits just stopped working after a while. he tried other sensors on the circuit and the sensors work fine in all the other circuits, so its something with that circuit. i just suggest to him to try and reprogram the pause time for that circuit as maybe its a programming problem and that may clear it.

i hope mine does ok. plan to set up a little test track on foam core with all the circuits being fired so i can let it run a while and test it out well.

so far im really happy with this little guy, hope it stays that way.


cheers

jeff

[Bernard]

I was looking all over on the internet for that unit and all I got was Miniatronics and it was at list price.

Jeff, you got a good price!

[cteno4]

I was looking all over on the internet for that unit and all I got was Miniatronics and it was at list price.

Jeff, you got a good price!

took a little while to get it thru engine tender as he had to order it then send it on. maybe 2-3 weeks total, but saved $20 and i was not in a rush! the chap at engine tender is very nice and easy to deal with. miniatronics is not very responsive. took three emails to get ahold of the instructions before i bought it and a couple of emails to see if they thought it would work just doing stops w/o reversing. they finally responded no that it had to do reversing in order for the stops to work. well my experiments show it will just keep doing stops if you want w/o reversing. in order to make this work though and not worry about tripping a reversing a proper value resistor (the value of a sensor out in regular light) in the reversing circuits to trick the system that theres a sensor there, but unlike a sensor, the resistor will never change value so the reversing is never tripped. i have not tried it w/o a sensor in the reversing circuits but i expect that would work also as you dont have to have sensors in any or all the stop circuits. i assume both the reverse and stop circuits behave the same in all ways except the reversing circuit just has the extra step in the code to reverse the polarity.

cheers,

jeff

[scott]

Jeff--it'd be great to see some video of this thing working if you eventually get the chance. I'm very tempted. I'm probably going to reserve one of the Toyama trams with Hobbysearch and start working on a way to work a tram line onto our layout. Or if we end up doing T-trak as well, it could work for that.

[cteno4]

ill post some of it working with fingers activating the sensors tonight.

on re-reading the instructions they say that you have to have the sensors in the reversing circuits for it to work, so looks like may have to try the resistor trick to see if that will work for a ttrak loop with stops only.

cheers

jeff

[cteno4]

Ok did some more playing with the system this evening.

one small problem with it is that if you are using the system for a reversing system with stops you will have the tram stopping at a slightly different point when it hits a sensor for a stop from the two different directions. as soon as the lead truck covers the sensor it will stop the tram (w/in an inch with the brake time). so for a short tram the difference is maybe two to three inches. for longer trams, though, this distance could be several inches (basically the length of the tram/train - the stopping distance).

this means you cant have it stop exactly at the center of a small platform from both directions on a stop circuit.

there is a bit of a work around for longer trains. i did find that if you put two sensors in parallel in a stop circuit you had to have both sensors triggered (covered) together to make the train stop. so you could have two sensors spaced at near the lenght of your shortest train and that would make the train stop in a much more closer spacing in both directions. problem with this is that if your train is shorter than the distance between the sensors it will not trigger the stop... good news is the sensors are cheap ($1-2 ea) you could have  multiple sensors mounted in the track (ie one in the center for short trams and two wider spaced for longer trams) and then just plug them in as needed for the train to be run.

another interesting thing is that you can wire two of the sensors in series into a stop circuit and the unit under normal room light will respond to each individually. this means you could actually have 10 stops with the unit (as long as any of the two sensors wired together are not w/in the 6 second lock out time)! with this there is an interesting thing you can do with the sensor lockout that happens once one of the sensors is tripped. if you have these two sensors spaced w/in 6 seconds of travel time the second sensor (in series with the first) wont get tripped after taking off from the first. this means in each direction it stops only at the first of the two sensors it reaches (it ignores the second if its w/in 6 seconds of travel time. not quite sure how to use this, but doable.

cheers,

jeff

[Bernard]

Jeff - Does this mean you have to design the path of the tram to the particular size of the tram you plan to use?
(Will it be hard to interchange trams that have different lengths?)

[Tenorikuma]

How well does this work in low-light conditions?

[cteno4]

Jeff - Does this mean you have to design the path of the tram to the particular size of the tram you plan to use?
(Will it be hard to interchange trams that have different lengths?)

Well this is going to be a problem for any track mounted sensor as the unit will stop (or start to stop with the break feature of this unit) when the sensor is tripped. this is usually not a problem for using it for only reversing as you just put the sensor near the far dead end of the platform so that longer trams fill the platform and shorter ones just stop near the end of the platform. in the past most units just reversed (a few did have some stop addition boards you could do, but they would have this problem too.)

it when you are using the stop circuits in between there is the problem as if you have one sensor for a stop, the tram will stop when it hits the sensor and from the two different directions the rest of the car will hang out to either side. so if your platform is two tram cars long and you mount the sensor in the center of the platform area the tram will stop at a position filling from the end it entered to the center. the brake feature of this unit softens things up a bit as you get like an inch of coast once it trips the sensor so your platform would not need to be quite (maybe minus 2") 2x the tram length in order for trams coming from both direction to stop w/in the platform area.

this problem gets harder if you use longer trams of course. one solution maybe to use 2 sensors in parallel on one circuit so both have to be tripped in order for the tram to stop. this way you could mount two spaced just under the length of your tram centered on the platform and then it would stop in the center of the platform from both directions. problem is shorter trams wont cover both sensors at the same time and thus would not trigger a stop. longer trams than the sensor span would also then stop a bit early and the extra length would hang off the back as above with the single sensor in the center.

another solution would be to put two sensors in a platform, one at each end, on a bi-directional platform and then use some gates diodes or transistors to sense the direction of the train and only turn on the sensor at the far end of the platform for the direction of travel. this may not be a biggie for me in the end as i may just have this on the ttrak and not use the reversing except at hoome on the wall. in that case the direction of travel is constant and i just mount the stop sensors at the far end of the platforms in the direction of travel for each track.

this is one of those things that automation brings up. some of the simplest sounding things can end up being nasty little problems to automate with sensor and control hardware from a program! we take for granted how good the human brain is at taking a little situation like this and just figuring it out intuitively. when you have to work out the data you need to gather, how to have your automated system gather the data, then the processing tasks needed to make it all happen you see its not always a snap! that automatic monkey brain is pretty powerful!

going to keep noodling on this more to see if there are some other solutions to be had. hope i dont blow this thing up experimenting! i am the mad scientist in the basement now as i have the train shop/room up and sort of working now!

cheers,

jeff

[cteno4]

How well does this work in low-light conditions?

Ill experiment on that tonight. works fine under the basement fluorescent lights that are not too bright. ill try shading the sensors and turning off the overhead lights and just turn on some photo floods in the corner of the room.

the good thing about this unit is that at power up it looks at each reversing and stop circuit and evaluates the resistance of each photo resistor (sensor) to see its resistance under the light it is currently getting. so if one sensor is right under a bright light and another one is shaded, the system knows the difference in resistance for each individual sensor needed to trip it.

these sensors are basically resistors that are reactive to light. the more light its getting the lower the resistance, the less light it sees the higher the resistance. so when the train rolls over the sensor and blocks the light the resistance goes up. this is what the system is looking for, an increase in resistance, to trip a circuit for stopping or reversing.

cheers

jeff

[Bernard]

i am the mad scientist in the basement now as i have the train shop/room up and sort of working now!

cheers,

jeff

Are you going to nickname your tram.... Igor?

[cteno4]

i am the mad scientist in the basement now as i have the train shop/room up and sort of working now!

cheers,

jeff

Are you going to nickname your tram.... Igor?

Yes and i am Froderick, not frederick. have not determined which end of the tram will have the hump though... Bleucher!

i have to LOL as young frankenstein is one of my fav movies. when i was young at the monterey bay aquarium we use to have folks come into the design warehouse before it was built (it was at the end of cannery row) asking directions. my little model shop was at the back door so i usually ended up answering these. one day i was pointing out to a lady where to go while i had a #11 xacto knife in my hand and after pointing let my hand drop to my thigh and sunk the blade into the front center of my thigh in perfect young frankenstein fashion. feeling the warm blood on my hand i quickly decided to get rid of the lady before pulling the blade out... bloody mess but ended up healing up well... nice scar next to the matte knife one, but thats another story...

[scott]

Ouch. Reminds of when I was building one of those Cub Scout "pinewood derby" cars and slid a x-acto saw blade all the way under one thumbnail when I slipped. :-P

[cteno4]

owch, thought that was to be done with bamboo splinters!

ok i about the same time i was drilling from under the big 3/4" scale architectural model of the aquarium with a 1/8' bit. i made the mistake of reaching up to hold down of the board i was drilling through and when the drill went through the board it also went through my index finger about the center of my fingernail. needless to say looking up and seeing the tip of the drill bit sticking out of my fingernail and realizing i was going to have to reverse the drill and back it out, it took all i had to flip that switch and hit the trigger! oddly enough no scar from that one...

jeff

[Bernard]

Been there, done that and the Emergency room knows my SSN by heart. I think they call be to remind me that I need a booster shot soon.

Seriously I hope you're alright.

[cteno4]

Been there, done that and the Emergency room knows my SSN by heart. I think they call be to remind me that I need a booster shot soon.

Seriously I hope you're alright.

LOL! actually never went to the emergency room with all the stabs, pokes, road rashes, etc over the years. probably should as stitches would have been good at times probably! always patched myself up and survived, but still many scars... afraid when i loose al my hair as a lot of bumps and scars will start to see the light of day for the first time. wont be a smooth dome on me, thats for sure! at 6' 4" and living and working on boats a lot i have more than my share of dome bumps.

i finally got to go to the ER the first time a couple of years ago for myself, but it was due to a tiny little kitty and a very small bite. i was at friends in california and petted the next door cat for a while and like most cats at some point it just turned around and bit me on the hand. not bad and i use to work with a vet friend capturing and fixing feral cats so this was absolutely nothing compared to with the thrashing i would get from that and never had an infection from bites and scratches, so i thought nothing of it. day and a half later my arm ballooned up! had to go in and get a big whomp of antibiotics to knock off the infection. probably the most minor wound i have ever gotten ended up getting me into the er!

a few years of doing exhibit and architectural models meant living with matte and xacto knives in my hands so lots of slashes, but all the fingers are still there!

cheers

jeff

[Bernard]

i finally got to go to the ER the first time a couple of years ago for myself, but it was due to a tiny little kitty and a very small bite. i was at friends in california and petted the next door cat for a while and like most cats at some point it just turned around and bit me on the hand. not bad and i use to work with a vet friend capturing and fixing feral cats so this was absolutely nothing compared to with the thrashing i would get from that and never had an infection from bites and scratches, so i thought nothing of it. day and a half later my arm ballooned up! had to go in and get a big whomp of antibiotics to knock off the infection. probably the most minor wound i have ever gotten ended up getting me into the er!


cheers

jeff

Did that too.... except it was our cat Mudpie who did a deep puncture to my calf. Had to have a shot and antibiotics. The leg did blow up but healed in a week.
You and I can compete for the Guinness Book of records for odd injuries.

[cteno4]

what got me is i have had lots of cats. when i was a kid we had all feral (wharf) cats on the ship that would befriend us and never a problem, lots of house cats, catching and fixing feral cats, never a problem. then a stupid little pint sized house cat with all its shots and a bite that didnt even make me flinch or draw blood sends me to the er for the first time!

ok how about taking off the last 3/8" of your index finger with a 24oz framing hammer (60d framing nail split in two and the hammer glanced over about a foot and nailed the finger end)! when i reached 40 the tip of the finger finally looked right. luckily i did it when i was 15 and the tiny bit of limb regeneration humans actually have is in the tips of fingers! young kids can actually regrow some of the distal phalanges if taken off. i may have lots a tad of bone but almost half the nail and skin at the tip of the finger. about a year till the tip was close to normal size, but looked odd. would watch the odd part slowly get smaller and smaller towards the tip of my finger over the years.

strangely enough like 5 yrs later my dad lost the same tip of his finger via a chain being pulled taught on his ship. he never grew back the end at all and still has the stubby finger.  so guess it pays to damage yourself as a kid now and then instead of in your adult years!

ok now its gotten way off topic here of reversing circuits, need to move this to a new thread of parts i have lots along the way...

cheers

jeff


 

[alpineaustralia]

Gee you guys are a barrel of laughs. You call that a scar?..you should see...

[Tenorikuma]

Did that too.... except it was our cat Mudpie who did a deep puncture to my calf. Had to have a shot and antibiotics. The leg did blow up but healed in a week.
You and I can compete for the Guinness Book of records for odd injuries.

When I was 17 or 18, I got a minor scratch on one shin from scraping it against some tree bark. However, a strange infection set into the muscle, and my shin became red and swollen to the point where I could no longer walk properly and had to stop working. I ended up having a wad of gauze inserted under my skin for a day to drain away the pus and going on a special antibiotics regimen for some time.

[cteno4]

ooooh we are now to puss! great stuff! in grad school the campus medical center dug a small cyst out of my neck and packed it with string gauze and sent me home with instructions to just pull on the loose end in a few days. well i did and it was like a tape work unraveling out of my neck for about a half meter... that one almost grossed me out!

i have some friends i travel with and one of them we talk blood, puss, etc at the dinner table while the other turns green at that sort of stuff. we always forget and launch right into good gory discussions and jim turns green...

cheers,

jeff

[scott]

Just so I have this straight--the 5-stop unit sounds like it has five stops in addition to the two reversers at either end of the line--is that right?

How many stops and reversers does the cheaper unit have?

[Bernard]

Scott - I can answer for the RU1-1 Unit. It only has a autoreverse at each end. The tram slows down but really doesn't stop. If you check out my thread on the unit I believe I list where you can purchase it for about $37.00 plus shipping. Direct from the manufacturer, Miniatonics w/shipping it's about $60.00. The RU2-1 Unit from Miniatonics is about $110.00, that price includes shipping.

[cteno4]

Scott,

the RU 2-1 has two reversing circuits (one for each end) and up to 5 stop circuits (for pauses along the way).

you wire a sensor (photo resistor) into a circuit that you want active. when a sensor is activated that circuit trips and either causes stop - pause - reverse - start or stop - pause - start. if you are doing a reversing tram set up then you can use all, some, or none of the stop circuits.

you can double up sensors in the stop circuits by wiring two sensors in series into a circuit. this way either sensor will trip the circuit and thus you can push the unit up to 10 stops if you really want them. only caveat here is that if you wire two sensors in series you will need to have both of them in ok lighting (ie normal room light, not a dim hidden corner or something like that).

the stop also is not a hard stop, but a nice little deceleration and the start is a nice little acceleration, sort of like having a break and momentum feature on a throttle. you cant adjust the acc/decel rates though, but what is there seems good for slow tram speeds that you would run at and looks a lot better than most reversing units which are just power on / power off (can we see folks standing in your trams going from 0-40 mph in less than a second!).

i got the ru2-1 for $85 shipped from the engine tender. took a few weeks as he had to order it then ship it, but the only place i found with a discount under the $99 msrp. nice guy and didnt take cc info till he had the unit ready to ship.

http://www.enginetender.com/475m.htm

cheers

jeff

[David]

The topic is old but it's been linked to a couple of times recently so it caught my attention....

Any photos of the unit/sensors? I can't find any on the websites linked (unless I don't know where to look). Pictures would certainly help figuring out how one could go about mounting/placing the sensors and if they'd work with an existing diorama.

[Bernard]

Here is what the sensors look like and I have the RU1-1 and the link to the forum:
http://www.jnsforum.com/index.php/topic,813.0.html

But I would spend the extra money and go with the RU2-1 that Jeff has because it can do multiple stops, the RU1-1 never stops just auto reverse.

[cteno4]

David,

yeah thats the problem with forums sometimes threads with good basic info can get buried! the ru21 is a nice little unit. gives you a lot of flexibiltiy for some simple automation in a pretty self contained unit. as Bernard showed the sensors are easy to pop into a layout, just small holes to put the leads and the sensor sits flat. you can even counter sink it a bit. the real beauty of this unit is it auto adjusts the sensor when you turn it on for the light level at each sensor location. all of the other units i have fiddled with required you to adjust the levels manually with a pot on the circuit board. bummer if the light in the room and or location changed!

the circuit board is simple. screw terminal sets for the input 12v wall wart and track power on one side. a screw terminal strip along the other side that has inputs for two reversing sensors and 5 pause sensors. in the picture i just have a few sensors wired straight onto the board here for testing. in the center there is a slide pot for your throttle. this is the only problem with the unit as its a bit akward from its location for mounting in some sort of project box. if you wire the terminal strips to some other sort of plug system it would ease this some.

all and all im really happy with the units. hope to have them all installed soon to the ttrak modules. also thinking about installing sensors in the kato unitram track sections as well. thats the beauty of this system, just get some extra sensors an you can plug it into any system. the unitram will be a bit more of a challenge as its thin, but think it shouldnt be too bad with some small gauge wire (dont need heavy wire for the sensors).

yell if you have questions!

cheers

jeff

[IST]

Hmm, interesting stuff.
I am wondering how could you hide the senzors in the Unitram baseboard. The idea is great, I can imagine that trams are running on the layout and the help with this unit stops and starts again. Would it be possible to make video about how it is working? Or could you mentioned any on Youtube or elsewhere. I haven't find any yet.

[cteno4]

dont have any sensors placed right now, just been testing with the sensors plugged into the unit (work on the new jrm layout sucked all my train time away lately). if i get some time this weekend ill shoot a little video of that. gives you the action of the brake and acceleration features in the unit. really is the best reversing/pausing system i have seen outside of really high end automation systems. simple and clean.

cheers

jeff

[underworld]

Looks very cool Jeff!!!    



underworld