TMCC loco stalling out on crossing

You didn't mention brand or degree of X, that can be very relevant.

Is the stay alive battery, bcr, etc good?

A change in rollers or an additional one is another answer. 

You might try a temp. jumper of a foot or so from chassis to outer rails and just run it over the X. That way you are sure if it is rollers or frame losing contact

measure the distance between pickup rollers.

and let us know by a picture or something else what kind of crossing you have so we can determine the dead distance.

bigdodgetrain posted:

measure the distance between pickup rollers.

and let us know by a picture or something else what kind of crossing you have so we can determine the dead distance.

Its a fast rack 90 degree crossover.  

Adriatic posted:

You didn't mention brand or degree of X, that can be very relevant.

Is the stay alive battery, bcr, etc good?

A change in rollers or an additional one is another answer. 

It’s a fastrack 90 degree crossover.  I have 18 volts continuous current so no back battery.

I'm guessing that both loco & tender have roller pickups.  If so, add a one- or two-wire tether between the loco and tender, effectively "bridging" the hot and ground pickups together.  This greatly improves your chances that at least one roller and set of ground wheels will be on a powered section of track.  As the other posters suggested, make sure all of your outside rails are firmly grounded.  You can measure them with a Volt-Ohm meter (VOM.)

I wired the tender rollers and engine rollers together and solved pick up issues on my Atlantic

Loco rollers are too close together, mine stalled on some atlas switches.

Ted S posted:

I'm guessing that both loco & tender have roller pickups.  If so, add a one- or two-wire tether between the loco and tender, effectively "bridging" the hot and ground pickups together.  This greatly improves your chances that at least one roller and set of ground wheels will be on a powered section of track.  As the other posters suggested, make sure all of your outside rails are firmly grounded.  You can measure them with a Volt-Ohm meter (VOM.)

Hi Ted

Tomorrow, I will run a separate hot from the tender to the loco and see if that will help.  

Thank You

  If it takes a battery, that will likely be the easiest fix. And it won't matter which power leg is dropping.

  If the power loss is because you are creeping across however, a change in rollers or addition of one may still be the only fix. The dropout prevention relies on momentum to get back to enough power for the motor, the battery only handles the board dropping into neutral again and again. The board wont drop out on a split second loss of power with the battery( and fyi, bcr is a capacitor that simulates a batteries function in this case. I.e. a rechargable battery without a huge reserve like a battery, and less likely to leak with age)

I do a tether between lots of locomotives and the tender, it typically fixes this issue 100%

gunrunnerjohn posted:

I do a tether between lots of locomotives and the tender, it typically fixes this issue 100%

Yes.

And, typically, this gap issue is on the center-rail part of the circuit, though the common side can occasionally be a culprit, especially in this age of insulating traction tires.

Batteries are for conventional-operation sound continuity in the Lionel system, so far as I know.

Batteries are also useful for many command locomotives, some of them tend to have sound dropouts when operating, especially the tenders with the wireless tethers, they only have two pickups.

gunrunnerjohn posted:

I do a tether between lots of locomotives and the tender, it typically fixes this issue 100%

Thanks John!