Confused: Connecting Transformer to TIU to FasTrack

@paulp575 posted:

In the past, I have wired my layout as follows:

.................................

Plugged in the TIU and used the DCS Remote to raise the track to 22.0 volts. Nothing!

Checked the power with my meter; it said no power. So I backtracked and checked the output power on the variable out. Only 3.9 volts!

Checked the power on the Fixed Out 1 and it was 19.2 volts.

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I guess my question is which output should I be using for this setup? I'd prefer to run ALL my locos (MTH and Lionel) using the appropriate remote, but don't think that's possible  especially with conventional locos.

 

That part I bolded sounds odd.  Are you saying you had zero volts at the track, but 3.9 volts at the TIU? 

Did you disconnect the track from the TIU and measure the TIU without the wires hooked to the track?  If not, you should.  If the TIU output doesn't adjust with just the voltmeter on the output, it sounds a lot like the TIU circuit for VAR1 died for some reason.

What is your track setup, just a simple loop, or something more involved? If the TIU works without the track hooked up as suggested above, you may have some sort of track anomaly (small wire causing a low resistance across the rails, something like that)

Without the TIU hooked up and without the engine on the track, check the resistance from center rail to outer rail.  It should be an open circuit (max reading on the ohmmeter) if nothing is shorted anywhere. 

Either of the setups from the manual pages should work fine if everything was fine(and it did apparently until your problem - so your hookup was fine until something changed), but you obviously have something going on here that needs to be troubleshot to find the source of the problem.

If you are only running command locos for the moment, you easily could use Fixed1, but I would not experiment with trying to do so until I'm sure the track is OK.  You are correct to use Variable if you sometimes run conventional locos.

Walk before we run.   Find the problem, then build back up to the full functionality you had once you identify and eliminate the issue.

-Dave

Before you go too crazy, open the TIU and check the fuses (4).

Have you tried Variable 2? If you read voltage at Variable 1 output I don’t think it is the fuse.

Try connecting the power directly to Var. 1 in instead of jumpering it and see if you get voltage out.

Check for a blow fuse in variable 1.   You are powering Variable 1 by jumping from Fixed 1.  If you have power at Fixed 1 but not Variable 1 to the track the circuit from Variable 1 is cut in the TIU

@Vinny26 posted:

Check for a blow fuse in variable 1.   You are powering Variable 1 by jumping from Fixed 1.  If you have power at Fixed 1 but not Variable 1 to the track the circuit from Variable 1 is cut in the TIU

also, unfortunately a variable channel may fail. So if you have power going into var 1 but you can't get anything out, try swapping those wires to variable #2. If it then works, variable #1 may be damaged. Do check the internal fuse though!

Sorry I haven't responded to any replies. Been down with a virus - covid-19! Not sure when I'll be able to sort all this out, but it is my number 1 item when I'm feeling better.

UPDATE:

Connected TIU to power (track not connected at this point) and had the following reading on the output side:

Fixed1: 18.9v

Var1: Started at 2.0v and slowly dropped down to 0.8v and held at 0.8v

Connected track to TIU via Var1 Out:

Fixed1: 18.5v

Var1: Started at 4.0v and slowly dropped down to 0.8v and held at 0.8v

Checked continuity at various points around the simple oval layout (no switches) - both with and without power from Var1 Out: 1.0 at all points.

When I turned on the remote and raised TR1 to 22.0v (track still connected via Var1 Out) reading was 18.5.

Thinking so far so good. Maybe it was just one of those glitches?

Anything else I should check before placing loco on the track?

Glad to see you are on the mend from CV19.