Voltage drops through ZW, TIU and layout.

I'm no electrical engineer, but one thing to check is if you have anything drawing a lot of current that could be dropping the voltage.  Do you have the meters for the ZW?  I have the meters and find them very useful..especially the ammeters. 

It is definitely not normal to have the voltage drops that you are having.

If I follow my voltages, they remain very constant.  I have 4 180 watt bricks.  The voltage from each channel of the ZW is 17.6 volts.  If I measure the track voltage at various locations, it is between 17.1 and 17.3 volts.  I also have a ZW-L.  I set it to deliver 17.6 volts at the outputs (it can go higher), and again, my track voltages are between 17.1 and 17.3 volts. 

I have the ZW's connected to 2 TIU's and after the TIU's, they go through the TVS-4 from Scott's Odds and Ends. Because it is an around-the-room layout, I have some feeds from the TIU's that are over 45 feet long.  I use 12 gauge for the long feeds and 14 gauge for the shorter feeds. 

What are you measuring with? True RMS meter? OScope?

Under load or no load on the track?

Why use the ZW and not just plug the brick into the tiu?

Tight connections? 

No full time meters on the ZW. Using a Blue Point digital multi meter to get the readings. The layout was powered up, but nothing running at the time of the readings. Adding the TIU to the layout was an afterthought, and I'm not sure I'm going to keep it installed. Nice to have if I grab a Proto 2 or Proto 3 loco but nothing on my roster at the moment. I suppose I should go through things again and check connections. Thanks for the insight so far. 

The voltage drop of a volt or a bit more is normal through the ZW-C, nature of the beast.  If I add a 8A load to mine, I get about 1.4 volts of drop through the PWC version, the board is the same in the version you have, so I'd expect the same voltage drop.  The same for the TIU, it'll drop the voltage through the variable channels as it also has drops internally.  The TIU should NOT drop any voltage through the fixed channels, if it does you have bad connections, either at the terminals or internally.

You could connect your TIU in passive mode, that would 1.3 of your volts back.  Also, run another feed to the far end of the layout, that will get you back another volt.  Most trains run too fast... what are you running that needs more than 16 volts?

Derek we pretty much run the same system:

ZW-C

4 180 watt bricks running through 4 channels of a TIU

We get a voltage drop of just a bit more than 1 volt. Seems that drop is coming from the electronics inside the ZW-C.

If we measure at the ZW-Z output, its about a volt lower than measuring directly from the brick out put. That being said, our voltage at the output of the ZW-C is the same as measured at the track. So there shouldn't really be any drop going through the TIU and out to the track.

wires?

connectors?

Your track voltage should read the same as the output of the ZW-C and/or the output of the TIU...which should be pretty darn close to the same.  

You will get a voltage drop through the variable channels of the TIU, even in fixed mode.  Figure on about .6-.7 volts of drop under load through the variable TIU channels.

Derek,

   Do not worry about the slight voltage loss, it means nothing as long as your trains have a 10 signal and they are operating correctly, the slight voltage loss is no big deal and everything remains safe.  

PCRR/Dave