mth o gauge dash 8 running over atlas switches

What size are your turnouts; O-72, #5, #7.5 or smaller? You may have a more complicated issue than powering each end of the turnout.

Are they new turnouts or the older ones. I have several older ones that needed to have each end powered.

The turnouts range from 36 , 45, 54, 72 and the combination 54/72 curve. My mth dash at slow speeds are getting stopped on pretty much  the group. Again I have track power going to two ends, my other math ps2 engine a BL-2 diesel has no problem. Thanks.

 

I bought some new others over internet.

 

Leeg

Do you have any of these switches back to back or connected directly to other switches? Sometimes when you do that the 'dead spots' (no power) end up just right with certain engines so no pick up rollers are touching.

One thing to try is when the engine stops, note where the pick up rollers are and see if there is power to either one. Also check both pick up rollers to make sure they are both working and that a wire hasn't come loose somewhere on one of them.

The curved switches probably all cause a problem with an engine or two sooner or later just due to the way they have to be made because of the curve and the distance between the powered rails.

How many rollers?

On my new dash 8 I have two rollers. Yes it seems that the curve 72/54 are causing the most trouble. but most of them do act up. when I try to run my dash. So far my NH ABA has not had the same problem. I'm powering the switches separate from track power. All told I have 23 switches on a 10 x 20 layout, two levels, using a math 4000 for track and a prewar train master for switches. I also seem to having up and down power issues, although I have 20 v going through the track. Guess I will figure it out one short step at a time.

Going to hook up my cmcc to mth TIU and AIU, but wanted most issues cleaned up beforehand. Thanks

 

Leeg

meant cmcc

TMCC

Well I have a rule of thumb.If you get "dead spots" add power drop.Done.Thants my 2 cents.Nick

Is this a PS3  2/3 rail ?

This sounds like an old RAILKING Dash 9 Diesel.

This sounds like an old RAILKING Dash 8 Diesel.

Sorry not to confuse the issue, first problem was getting my brand new railing PS3, dash 8 , not to stop on my atlas switches. second was to hook up tmcc to my D.C.'s and try out old tmcc engines.

Especially on my 72/54 curve switches. Other then power feed on all ends. Is there another solution?

 

leeg

Perhaps RailKing new Dash-8 have same problem as the old ones, 18.5 inches long pickups to far apart? Brand new Providence/Worcester PS3, thought they would of solved issues.  Any ideas let me know.

leeg

I have a lot of experience with Atlas switches.  I suggest that you get a simple voltmeter and check that all of the third rail sections are powered throughout the switch.  You may have to run a jumper from a powered third rail section to the dead third rail section.  Atlas switches, especially the older ones, are notorious for not passing power to all the third rail sections.

Another problem that seems to plague these switches is dirty track - especially the third rail.  I have found that just cleaning the track on the switch will allow engines to pass over them.  The switch can be dirty even when the other track is clean and engines are running fine on the rest of the track.

Another problem may be that the wheels are contacting both the outside and middle rail at the same time. This happens on some engines and not others.  This causes a short which stops the engine without tripping the power supply circuit breaker.    The way to find this problem is to turn off the room lights and watch for a spark as the engine goes through the switch.  You can see this best when the engine has some speed.  Place a short piece of insulated tape on the rail where you see the spark to see if this solves the problem.  Several of my switches have pieces of insulating tape installed on the running or center rail.   

A third problem that happens with all switches is that some engine rollers are spaced so that both are on insulated parts of the switch.  Sometimes this can fixed by turning one or more of the engine rollers around or installing an extra roller on the engine.   

If all else fails, you may need to use a relay to power one of the running rails depending on which way the switch is thrown to fix this problem.  This is a last resort solution and requires connecting the relay to the switch machine.  Try the other solutions first.

NH Joe

New Haven Joe posted:

 

If all else fails, you may need to use a relay to power one of the running rails depending on which way the switch is thrown to fix this problem.  This is a last resort solution and requires connecting the relay to the switch machine.  Try the other solutions first.

NH Joe

I've attached the Atlas wiring diagram for the above solution.

Thank you I will try these suggestions the simpler ones first

 

leeg