Trains.com

How to wire a lionel 81 rheostat

6481 views
13 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    October 2015
  • 114 posts
How to wire a lionel 81 rheostat
Posted by Toy Trains FTW on Monday, November 27, 2017 2:29 PM

I recently purchased an 81 rheostat and I dont really know how to wire it.  It is complete and I was screwing around and wired it to the ground wire from my transformer and it seemed to work but it got really hot after 10 minutes from under 18v.  Did I do this right or am i supposed to wire it thru the hot wire?  Also Becky if you see this I saw an article about you in a ctt magazine lol

  • Member since
    December 2001
  • From: Austin, TX
  • 10,096 posts
Posted by lionelsoni on Monday, November 27, 2017 2:52 PM

Connect the transformer common terminal to the outside rails.  Connect the other transformer terminal to one of the rheostat terminals.  Connect the other rheostat terminal to the center rail.

Bob Nelson

  • Member since
    October 2015
  • 114 posts
Posted by Toy Trains FTW on Monday, November 27, 2017 3:11 PM

alright so i was supposed to use the rheostat on the hot/red wire.  Thanks!

  • Member since
    December 2001
  • From: Austin, TX
  • 10,096 posts
Posted by lionelsoni on Monday, November 27, 2017 4:19 PM

But keep in mind that it's normal for it to get hot, which is why it's wound on that ceramic rod and covered with the metal cage.

Bob Nelson

  • Member since
    September 2010
  • From: Parma Heights Ohio
  • 3,442 posts
Posted by Penny Trains on Monday, November 27, 2017 6:48 PM

I use the 95's (but that's really only because I don't have any 81's.  Wink) but they work the same except the 81 has a lever and the 95 has a button.  The 88 is another story because that was designed for use with batteries and doesn't have a cover over the coil.  Anyhoo, if I can't mount them to the layout, I use a small block of wood and extra long wire to act as a "remote throttle".  Smile, Wink & Grin

The standard gauge is wired to a type K 150 watt transformer set at 24 volts by the way.  It's the only way I can get this basket case motor moving!  Laugh

P.S. That's "Mount Saint Garage Sale" over on the right restricting my standard gauge to an "around the legs" layout.

Trains, trains, wonderful trains.  The more you get, the more you toot!  Big Smile

  • Member since
    October 2015
  • 114 posts
Posted by Toy Trains FTW on Tuesday, November 28, 2017 10:22 AM

Ok @lionelsoni I guess thats why they stopped using them lol and @penny Im probably going to mount mine to a piece of wood with a transformer.  I also have a type K and love it alot but im currently using a type T... Woah 24 volts for the im assuming an 8(e)?  My 402 runs at 3/4s of the way on my rheostat with a max setting of 18v lol(love the box cab btw)

  • Member since
    September 2010
  • From: Parma Heights Ohio
  • 3,442 posts
Posted by Penny Trains on Tuesday, November 28, 2017 7:21 PM

Yeah, but most supermotors didn't have battery acid leaked on them!  Tongue Tied  I did the best I could, but it's far from perfect.  Wink  It also wobbles!  Laugh

Trains, trains, wonderful trains.  The more you get, the more you toot!  Big Smile

  • Member since
    March 2015
  • 2 posts
Posted by ljliberto on Wednesday, February 7, 2018 12:29 PM

Can you take close up picture of your 95 with the wires attached?  I just bought one and want to make sure I am connecting it correctly.

 

BTW, I love the Lionel logo on your table.

  • Member since
    September 2010
  • From: Parma Heights Ohio
  • 3,442 posts
Posted by Penny Trains on Wednesday, February 7, 2018 6:17 PM

Trains, trains, wonderful trains.  The more you get, the more you toot!  Big Smile

  • Member since
    December 2001
  • From: Austin, TX
  • 10,096 posts
Posted by lionelsoni on Wednesday, February 7, 2018 6:31 PM

ljliberto, I don't have a picture to show you.  But, if I did, it would just show two wires, each wire connected to one of the only two terminals of the rheostat.  See my post above for what the other ends of those wires would be connected to.

Bob Nelson

  • Member since
    August 2010
  • From: Henrico, VA
  • 8,955 posts
Posted by Firelock76 on Wednesday, February 7, 2018 7:31 PM

Penny Trains

 

Wow, that's impressive.  Like a corner of Castle Frankenstein.  All those antique electrics...

  • Member since
    March 2023
  • 2 posts
Posted by madman on Monday, March 6, 2023 10:18 PM

I recently aquired a #95 rheostat.  I thought of using it in conjunction with my ZW transformer in order to slow down a few post-war accessories, without having to adjust the ZW throttle.  However, through experimentation I discovered that the voltage range put out through the rheostat, wasn't fine enough for the task.  

  • Member since
    December 2005
  • From: Hopewell, NY
  • 3,230 posts
Posted by ADCX Rob on Tuesday, March 7, 2023 11:17 AM

madman
I discovered that the voltage range put out through the rheostat, wasn't fine enough for the task.



That's because, as you have discovered, the rheostat is a current limiting device rather than a voltage reducing device.

As the load in the circuit rises, the effect of limiting the current will be a drop in voltage, but this will not manifest in your light duty application.

If you power a single #53 lamp with the rheostat, you will find that it does not dim the lamp at all.

Rob

  • Member since
    July 2020
  • 1,620 posts
Posted by pennytrains on Tuesday, March 7, 2023 5:43 PM

I've always wondered how it worked considering my super motored #8 needing at least 22 volts to move at all.

Big Smile  Same me, different spelling!  Big Smile

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

FREE EMAIL NEWSLETTER

Get the Classic Toy Trains newsletter delivered to your inbox twice a month