TMCC Direct Lockon #6-34120 Hookup

The Lock On is like a fuse so you will need one for each transformer output that is connected to the track. Also its set to trip at ten amps so any fuse or breaker lower than that number will blow or trip first.

Given current prices the Lock On cost nearly the same as a DCC Specialties PSX1-AC breaker which is far more flexible than the TMCC Lock On.

Pete

The TMCC lockon is very fast, but a quick blow fuse might be faster.  The power adapter cable is made to go with the TMCC PM, which may be slower than the TMCC lockon requiring the fuse.

Other than cutting the adapter cable to get rid of the fuse (you may not want to do that), I would look for some other Molex adapters like those found in the TPC cable set #6-14194 which do not have a fuse.  Some forum members have them for sale, or you can search for them (you can also make your own, search the forum).

Maybe a higher amp rated fuse might let the lockon go first.  (ADDED: see Norton's response above).

It sounds like you are all Lionel.  FYI, a few forum members have stated the lockon degrades the DCS signal a bit.

ADDED: Concur with Norton that a PSX is a much better choice.

D.E.,

In the configuration suggested/implied by by the manual that fuse is there to protect the Direct Lockon from melting if it fails and short circuits internally.  Next down the line the Direct Lockon is there to protect your trains on the track from a short circuit that would occur downstream of the Direct Lockon.

As has been pointed out, if the fuse's value is smaller than the trip current of the direct lockon then it will blow first.  It should be larger instead.  I'm almost certain that the inline fuse holder in the cable came with a fuse that is too small because it was originally designed for another purpose (to be used between a transformer and a Power Master) and was never updated.

Select a higher value fuse and you should be ok going forward.  If the Direct Lockon opens the circuit at 10 amps, use a 12 or 15 amp fuse instead.  While 12 to 15A seems high remember it's job is to stop a melt-down in the Direct Lockon and not in the track or train.  12 to 15A should work fine for it's intended purpose.

M.H.M.

If you ever plan on running MTH DCS command stuff, I'd rethink the TMCC Direct Lockons, they kill the DCS signal.

As others have said, go with the PSX1-AC for each power district, a better choice.

Thanks guys.

Great and very helpful information and suggestions. Yes, I am all Lionel except for a few pieces of rolling stock from other manufacturers. I will try going with a higher amp fuse first and see if that works. - Thanks again.

Hi

Two years later but in a similar boat!

i have new ZW(L) connected to four track power loops.  Have fully refurbished ZW(R) phased to track common ground with four outputs intended to be ‘fixed voltage’ 12v for: A is all 22 switches; B is all 10 uncouple / operating tracks; C is all signals (full count and install) not yet completed); D is for LCS power to about 9-14 devices (4 ASC2, 3 BPC2, 2-4 Sensor track, 2 STM2, wIFI).

Have on all terminals of above ZW(L) and ZW(R): TVS Diodes (4) 1.5KE36CA - ZW,ETC

I bought 4 new TMCC lockons and 4 new power adapter cables (as instructed by Lionel) both one for each ZW(R) output. Set TMCC lockon voltage to 180w, not 135v. Getting trips at less than 12v settings on ZW(R) throttles, even just one throttle at a time.

What’s up?

Based on this 2021 discussion I am guessing I cut out the power adapter provided fuse and replace it in line on the adapter cable with stronger say 15 amp fuse????

Is this a solution or a bandaid? Can these Lockons work, or do I scrap them for another preventive?

What do I do? Please advise. Thanks in advance.

- Ken

The TMCC Direct Lockon is intended to be used in command mode, hence the name TMCC Direct Lockon!  That being the case, they don't work properly at low voltages.

In addition to that, they have other problems.

They kill the DCS signal, so don't plan on running MTH DCS locomotives in command mode!

Also, they would randomly trip whenever a number of locomotives came close to the power drop in a simple loop of track.  That included both TMCC upgraded engines, factory TMCC and factory Legacy engines.  I deep-sixed the useless things and never looked back!

@gunrunnerjohn posted:

Also, they would randomly trip whenever a number of locomotives came close to the power drop in a simple loop of track.  That included both TMCC upgraded engines, factory TMCC and factory Legacy engines.

John,

As far as I can recall you haven't mentioned this before.  (I don't recall seeing it in your previous posts over the years, although I may have missed it.)

They seem to work fine for me, but now I know what to look for.  This will put me on the lookout.

Mike

Mike, I haven't had these for many years, I encountered those issues probably ten years ago, and that's when I banished those from my usage.  Truthfully, I see no reason for their existence if you're using the PH180 bricks.  I already have a great circuit breaker, and I am not a fan of my circuit protection continually pounding the device over and over again with power if I have a short.  I want to resolve the issue before I power up again, so the TMCC Lockon fails on that account as well.

John and Mike,

ok, I accept this conclusion. I will sell or trash 4 brand new TMCC Lockons - anyone want to buy?

Since I am all Lionel, migrating to Legacy, and will run factory Vision, factory Legacy, factor TMCC, and conventional … what if anything should I do?

I know it’s up to me to solve, just hoping you guys with all your experience can ensure I don’t blow it a second time trying to be preventive and proactive protecting these expensive engines. Obviously listening to Lionel was not optimal. I need your expert help, please!

In my case, with a ZW(L) powering the tracks, and the ZW(R) powering the extras in those few tracks (switch machines, extra rails and magnets in Un-couple / Operating tracks, plus signals and LCS modules interacting with track, I have these two questions:

1. Do I need any protection between the ZW(R) and what it is powering?

2. What more is needed between the ZW(L) and the 4 track loops?

Please advise! If you want to interact off- line please let me know - I welcome your interaction.

Thanks, Ken

Ken, for the ZWR outputs (or any Postwar transformer), I highly recommend Airpax Instant Breakers  and TVS diodes. If you're looking for the ultimate in protection for your Legacy locomotive's electronics, installing TVS diodes inside the locomotives, on the PCB track power inputs is the best way to protect their sensitive electronics.  TVS installed on the transformer outputs is a good step, but high frequency voltage spikes will travel past these.

Here's a link to the Topic started by Adrian and his explanation of how this happens:

Words about TVS Placement (Edit fixed broken link)

from that topic:

@gunrunnerjohn posted:

Mike, I haven't had these for many years, I encountered those issues probably ten years ago, and that's when I banished those from my usage.  Truthfully, I see no reason for their existence if you're using the PH180 bricks.  I already have a great circuit breaker, and I am not a fan of my circuit protection continually pounding the device over and over again with power if I have a short.  I want to resolve the issue before I power up again, so the TMCC Lockon fails on that account as well.

I anticipated building a fairly large around-the-room layout and bought several PH-180's to get started.  For these I agree that there's no need for the direct lockon.

But in the course of buying lots of other miscellaneous stuff, used, including accessories, TPC's and other things, I ended up with 5 or 6 PH-135's which were thrown in by the sellers with the deals, and these obviously don't have the internal protection that a PH-180 has.

The direct lockons work fairly well with the 135's but do have at least two of the issues you've mentioned in the past, namely squashing the DCS signal, and not having a manual reset.

I have not had the mysterious shuts-off-as-train-passes problem, at least not yet.  It may come.

Thanks for helping all of us with these kinds of things, especially the newbies.

We were all newbies at one time.

Mike

Steve,

[A] Sounds like you suggest Airpax Instant Breakers on the four low 12v outputs of my ZW(R) - correct?

- I have the TVS diodes (see earlier note by me on this thread which diode model) on the ZW(R)s output pairs of hot/ground already.

- What size and speed on these Airpax breakers would you suggest starting with?

[B] Is the newer ZW(L) transformer good on its own, where I also have the same TVS diodes on each transformer output pair of hot/ground?

- Ken

@Ken Gillig posted:

  [A] Sounds like you suggest Airpax Instant Breakers on the four low 12v outputs of my ZW(R) - correct?

Yes.

@Ken Gillig posted:

- I have the TVS diodes (see earlier note by me on this thread which diode model) on the ZW(R)s output pairs of hot/ground already.

- What size and speed on these Airpax breakers would you suggest starting with?

Ken, sorry I overlooked the part in your earlier reply where you already have TVS on the ZWR outputs.

Regarding the Airpax Instant Breakers, please follow the link here > Airpax Instant Breakers to a Topic in which I've outlined which models I recommend and where to buy them.

@Ken Gillig posted:

Have fully refurbished ZW(R) phased to track common ground with four outputs intended to be ‘fixed voltage’ 12v for: A is all 22 switches; B is all 10 uncouple / operating tracks; C is all signals (full count and install) not yet completed); D is for LCS power to about 9-14 devices (4 ASC2, 3 BPC2, 2-4 Sensor track, 2 STM2, wIFI).

With the understanding that all your track being discussed is FasTrack, based on your Topic, link here> What (if any) LCS Modules Needed for Legacy Switch and Block Control? , My thoughts on circuit breaker Amperage values for each ZWR output (A thru D):

A) 5 Amp   PP11-0-5.00A-OB-V

B) 5 Amp   PP11-0-5.00A-OB-V (with supplementary PTCs installed in series with the electromagnetic coils in the uncouplers/operating tracks) Link here> Bourns MF-R050

These will help prevent the coils from melting if they stay energized too long; ie. more than a few seconds.  Link here to discussions> Fastrack Operating Track Wiring and Issues and FasTrack Uncoupling Track - Not Compatible with LC/LC+ Out of the Box

C) 5 Amp   PP11-0-5.00A-OB-V

D) maybe 5 Amp   PP11-0-5.00A-OB-V, but I'm not entirely certain if this would be ideal.  Maybe someone with more familiarity with the LCS system could offer more insight into the current requirements for "about 9-14 devices (4 ASC2, 3 BPC2, 2-4 Sensor track, 2 STM2, wIFI)"

@Ken Gillig posted:

[B] Is the newer ZW(L) transformer good on its own, where I also have the same TVS diodes on each transformer output pair of hot/ground?

It's my understanding that the circuit breakers in the ZWL are very good, however

I would like to reiterate that because Transient Voltage Spikes caused by derailment occur at very high frequencies, they have very short wavelengths.  Because of this where TVS diodes are only installed at the transformers, these spikes can still be at damaging voltage levels at the trains' electronics (for a better understanding of this, please refer to this Topic (link here>Words about TVS Placement) .  This is why it's best to install TVS diodes inside the locomotives, right at the track power inputs into the circuit boards.

Here's a picture of the TVS diode I installed inside my TMCC 611J 6-38065.

I hope this helps!

Hi Steve,

Thank you very much for a very thorough recommended set of actions to my challenges and questions. This will be very helpful!

You are a "Layout Guardian Angel" for a relative newbie to advanced model railroading.

Ken, you are most welcome.  Thank you for one of the nicest compliments I've received here on the forum.

Steve,

I hope the "LGA" acronym I used does not stick ... for your sake!

Still, taking action now on getting the instant Airpax breakers. I just bought more TVS diodes for selected track points, and i will get the Bourns MF-R050 for 8 uncoupler/operating tracks and 8 uncouple tracks in my sidings for when I install them as I lay track.

I may even have to go to electrical trade school soon  .

Thanks, Ken