No output from TIU variable channels

Do you have the TIU's set to the same address? You may be confusing them. Make sure that your TIU address are different by checking the red light inside the TIU, when you power them up they will blink. Count the number of blinks on each TIU, this is the TIU address. Then set them to different address if they aren't already. Next make sure that all the channels are turned on for fixed or variable I am assuming you are going to use them all as fixed channels. Then set all the TIU's into super TIU mode otherwise when your locos leave the jurisdiction on one TIU that they are initially associated with you will lose control of the engines

Is the tiu turned "on"?? there are 2 ways to turn it "on"  . power to fixed 1 or an aux power supply  else nothing works including the var channels.

As Gregg says, how is it powered?

As Matt asks, are they different numbers?

Did you discover the cause of the blown fuse?

I have it powered by aux power power, by a z1000 brick. 

I have checking the blinking lights on tiu and one is #1 and the other is #2. I have not powered them up at the same time.

I have no idea what blew the fuse. 

Fixed channels work fine. Dcs signal is good on fixed. 

I haven't set it to super yet.  I have tried to used the variable channels in the passive mode, I have track power but no dcs signal. 

 

What is watt rating on a tiu?  I have two bricks at 185 watts for a 370 watts and then the zw-l for what ever watts, so I am for sure over 500 watts, if that could be an issue. 

If it is a Rev L TIU there is a chance that the VAriables are blown  We have replaced 6 TIU Rev L's because of the problem

180 watts per channel or 10 amps at 18 volts

Is there a sure way to tell if they are for sure blown? Yes, they are rev L.  I am relying on my transforms to protect my tiu, should I be doing more? 

We have had nothing but trouble with the Rev L variable ports   The Power FET's are the problem   MTH had two of our bad ones for over 4 months trying to figure it out.  They wound up just sending us two new ones which one had the same problem

Sound like the same thing, I have going on. I have 5 aiu connect to work my switches. I don't want to send them off, I guess I'll have to use the fixed of the two tiu, to get 4 loops. 

Had an early TIU loose the two variables. Just used the fixed after that and varied the voltage at the transformers.

 

A question for all, are the two variables more fragile when used as variable and more robust when they are set to full voltage?

I don't think it makes any difference.  The variable channel FET's still have to pass the current for the load connected to the variable outputs.

Hadn't heard of this problem with Rev Ls.  Glad I ddin't sell my solid old Rev Gs.

Failure of the variable channels of the Rev L was the topic of a couple of discussions for a while last year then went away. Did not seem to be a big problem expect for a couple of forum members.

 

However, because of this potential issue I have my Rev L TIUs setup in passive mode hoping this will not be a problem when there is no power going through the channels.  My layout control is via Lionel products, so I use my TIUs for engine control only.

I am running both legacy and dcs through the tiu.  I'll think twice before investing in more dcs control. 

Ron I'm curious were you able to get a good  DCS signal with the var channels set to FXD in passive mode?   Of course the tiu must be turned on.

 Testing the var channels might go something like this ... Power to fixed 1 or an aux power supply to turn the TIU "on"

 

Full power to VAR 1 IN     select Menu/ System/ DCS set up/ select the or high lite VAR 1 and select FXD..... There is a slight delay and after a couple of seconds  VAR 1 out should come to life.... repeat with var 2. If you get voltage it's time to add a engine or do a track signal test. good luck

 

 

Thanks Greg, I have already tried that.  

Is version 13a, the more reliable one?

How do you run Legacy through a TIU  I don't understand

Just ocurred to me.  There is a rare software bug that may be the cause.  Call MTH.

My track power runs from the tiu, I hook up a wire from the binding post of the legacy base and attach it to the all of the negative outputs of the tiu.  

Thanks Rjr.  I am heading to York and will be attending the DCS meeting and plan on getting all my tiu and hand held controllers updated.  I hope they have the fix for the bug you mentioned. For now I am just running four loops attached to the fix outputs of  two tiu's. 

Lord willin' & the creek don't rise, current plan is that I'll be one of the upgraders at York.  Hope to meet you there.  Look for the cantankerous looking guy at the upgrade table.  Hopefully, the V 5.0 mentioned in another thread will be available by then.

 

I'm checking with a contact to see if this sounds like the very rare bug.

 

You ought to move to Virginia.  I take the boat out all year, except when the river is frozen, which is usually only for a few weeks.

So Legacy really isnt't going through the TIU   Just checking because that is a problem.  The Rev L TIU Variable ports are a major PITA  They have failed so many times that we switched to Passive mode  We still had a problem with one  We might even try to double up every TIU and just used Fixed

I know I should move, but family is all here..... I do curse my ancestors  for not having started out south!!!!