Help with powering sc-2 controller

[Brent-o-27]

Hi,

Im taking on the task of restoring my train set now that i have a little toddler its a o-27 train but only o-42 or greater track. i have 11 lionel switches and have two sc-2 controllers. so i figured i was good 6 on one and 5 on the other. but my problem is i just have to use this capacitor discharge thing i have read about on here as i hate having to here the buzz and all the sparks now that im running cmd. but having reading the manual it looks like i cant use all 6 spots if the switches are going to not have constant power?? i qoate. Do not use the wall pack or the separate power terminals on the SC-2 if you are using it to operate switches. 

 

is there a way around this. i really do not want to buy another sc-2 they are cery expensive in canada. also if you want to se my layout you can check out the video i posted on my youtube channel. https://youtu.be/3buUutx_xlg

thanks

[Firelock76]

I can't give you any advice on those sc-2 controllers, but I just want to say I watched your video and that's a fine layout you've got a-building!

I like your UP RS-3, I got a Susquehanna one myself a few weeks ago.

[Penny Trains]

I agree, great looking track plan!  And aboard!

Becky

[Brent-o-27]

thx its fun to get it going again! i hope i can find a solution to the sc-2 as it would be a lot of fun to get them running remotly. 

[Laurastom]

Brent, I am not sure I understand your question. I am assuming you have two ASC2's. The ASC2 has two modes, Switch and Accessory. To operate turnouts the switch mode is used, in this mode only 4 turnouts can be operated by one ASC2. The power supply is required for operation of the ASC2 electronics and relay coils. It is isolated from the output contacts that actuate the turnouts.

If you have the older pre-Legacy controllers they operate differently and cannot be directly controlled from the iPad or Cab2 without installing what I believe is the LCS SER2 module.

[Brent-o-27]

i do have all older stuff as it was aquired in like early 2000s i think but never used. i have the original cab 1 pluse two sc-2 they are called. they can operate 6 switches each. and as i have 11 switches the plain was good. but now that i read the manual 12 years later i realize that i dont think i can use all 6 spots as the first spot powers the unit from the switch power and my switches will not be consitant power they will be dc run from a capacitor. here is the manual for the unit i have. https://www.lionelsupport.com/media/servicedocuments/60607229802501.pdf

its annoying to only get 5 spots plus i have to skip number 1 and number 7  im wondering if i can run another hot wire to the terminals with out messing up the switching operation  

 

[Buckeye Riveter]

Hi Brent,

I have three (3) SC-2 Controllers that run switches and accessories on my layout. One of the SC-2 Controllers runs six (6) switches.  This controller gets all its constant power from the track.

The second controller runs only accessories.  It uses a wall pack for power.

The third controller runs both accessories and switches.  This controller uses the constant track power to activate the SC-2.    

I believe I had to read the manual about three times to figure out how the SC-2 works.  It is very poorly written, so don’t feel bad.  It appears that if you are not going to use track power to activate the switches, you will need the wall unit, but first you need to program the SC-2 correctly.  I don’t know why the manual doesn’t tell you to program first.  I just plugged the SC-2 into the wall pack, flipped it to program and then programmed.  It stayed programmed after it was unplugged and then wired for actual use.  Also, you must make sure the switch is not powering the SC-2.  Remember the green light is to shine if powered correctly. When I change over to conventional running, i.e., the TMCC Cab-1 is varying the track power, the switches will barely operate because I’m using track power to throw the switch.  

[Brent-o-27]

thanks for your input. so for  sake of argument if I had six switches including the first switch set up using variable power in conventional mode i.e. and I also had the wall plug plugged in you don't think that would damage the Sc-2.  I will not actually be using variable power I'm going to use capacitors to stop the switches from humming but in essence the power will not be constant. 

[lionelsoni]

I think Brent's caution is justified.  Unfortunately, without a schematic diagram, it is impossible to be sure just what is inside the SC-2; but here are some guesses:

The instruction manual says not to try to power the thing both through the turnouts and any other way; but, if using it for turnouts, to make sure that one of them is turnout number one.  That tells me that the insides of the SC-2 draws current from the supply powering turnout number 1, through either of the turnout coils, in the same way as some traditional controllers draw current to power their indicator lamps, but not enough to throw the turnout.  If this is correct, then the 5 remaining SC-2 terminals should be available, with number 1 unused and the SC-2 powered by the wall-wart or its own power terminals.

Unfortunately, this adds up to 10 turnouts, not 11.  Is it possible that you could wire at least 2 turnouts to throw together, perhaps at a crossover?  If my hunch about how number 1 is wired is right, there is also the possibility of opening an SC-2 up and disconnecting the diodes or whatever that are connected to it.

Another concern is whether the SC-2's internal switches are metallic relay contacts or semiconductors (like triacs).  If the latter, the switch may not reopen after throwing, because of the continuing DC current supplied by the capacitive-discharge circuit.  Trial-and-error is called for here.

[Buckeye Riveter]

Brent,

Remember that the TMCC is a system.  It works the best when everything is set up to run in TMCC. This means constant voltage in the track.  When people try to mix and match, it seems that experimentation is needed because there are many variables. When you ran the legacy locomotive in the video, you did use constant voltage in the track, didn't you?

I believe there is a special section in the SC-2 manual that address the Lionel Switches. I do not have Lionel Switches, so I cannot address how they actually are powered or operate.  

I do know that if the external switch lever is lighted and the switch is not connected to the SC-2, the switch must be providing the power to light albeit very dim, the external switch lever.  If then the SC-2 was connected, I would presume that it is getting power from the track and it is not constant power as required to work properly.

BTW, here is one of my videos: https://youtu.be/W52fbZRGy-A  Notice the lamps on the switches and track connections are burning bright with constant voltage in the track.   When I change to variable power in the track the bulbs are dim and the SC-2 has trouble throwing the switch. I have never plugged the wall pack into the SC-2 when I am running in conventional mode (variable track power).  

In this video, https://youtu.be/1ICryXIW0mA we are running the Williams locmotive in conventional mode (varible track power).  At this speed notice the dim switch lamps, the lever lamps and track power lamps.  We did not use the SC-2 to throw switches.  We did it manually and kept the route simple.

[Brent-o-27]

thanks for your input. i also figured the same for terminal 1. and i also watched a lionel video yestorday that talked about wiring two switches together. i dont know why i did not think of that. but i do have two switches that if one is switched the other would always be as well so that will work i will use terminal 2-6 on both with the wall pack. i really hope there is not a problem with the capacitor idea and the sc-2. if it does not work. do you think a polyfuse of the correct size would work as a replacment for the capacitor idea?? i done know enough about electronics to know without trying it. 

[Brent-o-27]

Just wanted to update this with the info i have figured out. the switches run great off a cheep 12 volt dc power supply and the sc-2 works well controlling them. other then not using the first terminal so it does limit to 5 controls. but with dc the switches dont hum at all which is super nice. 

[lionelsoni]

That's good news.

You can use that same DC supply for the capacitive-discharge circuit (charging a ~5000 microfarad capacitor through a number-53 lamp).