Ammeter

You can't monitor the current for an entire ZW on one meter, but you can monitor each individual output.

Just be sure to hook them up like this...

Ok, that's what I thought, until I saw a photo of one user that had four voltmeters and one ammeter in a nice custom box (another thread on this forum).  Thank you for the quick reply.  Guess I will order 4 of each......

J

Rich, put your editor hat on for a minute.

Do you have 4 different loads (tracks) that you are trying to monitor voltage from, because if that's the case and you have one common (ground) to all loads, then in this case the ammeter would go across the common wire (in series) to one transformer. I am assuming that you have multiple throttles (as in a ZW). If you are using more then 1 transformer, then each load has to be tied into a separate ammeter and each volt meter would monitor voltage  from each throttle of that transformer. I'm not sure if I was able to help you because you aren't giving enough info as to how you have things hooked up currently.

Steam Forever

      John

Wow, I didn't think of inserting the ammeter on the common side and assumed the ammeter would go in series on the hot leads for each track.  

Yes this is a ZW, as listed in original post.   I'd like to monitor all four voltages and totalized current, so what you have suggested is perfect!  Thanks.

All four tracks are to a common ground and run to a single U connector, so the ammeter would be really easy to place in series.

I only have one transformer (for now).

John H posted:

Rich, put your editor hat on for a minute.

LOL! Good catch!

I fixed it.

Buy the ZW volt/amp meter they made about 10 years ago. It's internally wired incorrectly and does exactly what you are asking for as long as all tracks are common ground together. Hopefully someone here can confirm. 

Rod Miller

I was looking for one of those Lionel ZW meters, but can't find them.  Then I read some articles about problems with them, so decided to just build my own with a more nostalgic look.

romiller49 posted:

...the ZW volt/amp meter they made about 10 years ago. It's internally wired incorrectly and does exactly what you are asking for as long as all tracks are common ground together...

When used on common ground layouts, this meter will register about the same current on every ammeter display because the current is measured on the "U" returns. The voltage displays are accurate.

What this means is that if you have a large current draw on one power district of 4 connected to corresponding (A-B-C-D) and "U" posts, it will inflate all 4 current displays rather equally. For the total current being used at any one time, you have to add up all 4 displays.

If you use just one "U" connection, and this is the only transformer being used(none phased to it), then connect all commons to the one "U" on the meter, it will give you the total output of the transformer in whichever display(A-B-C or D) matching that "U" post. The remaining 3 ammeter displays will remain blank regardless of throttle settings and voltage displayed..

Something like this shoud do what you're looking for:

A separate Amp meter for each line is probably more useful over all, but this should get the job done.  As a note, you'll probably want to use a rather heavy gauge wire to connect all the U posts together, continuing with the large gauge wire through the amp meter, and then to a barrier strip to which each of the separate track main feeds can be connected.  

As a note, I placed the common for the meters between the track and the Amp meter.  This way they will report closer to the voltage that is actually on the track.  Placing the volt meter common side between the transformer and Amp meter will report a slightly higher voltage, as the Amp meter puts a slight drain on the line.  It's not going to make a huge difference, but it is a difference none the less.  

JGL

Perfect!  Exactly as I was envisioning the connections.  

One question John.  Why do I have to use a heavy gauge wire to connect all the U terminals together?  I thought they were internally connected.   My current setup has all the track commons connected at a buss bar and only one heavy wire running to a single U post.   I didn't jumper the U posts as I didn't think it was necessary.

J

zigzag930 posted:

...Why do I have to use a heavy gauge wire to connect all the U terminals together?  I thought they were internally connected.  

 That's a good idea to distribute the load over the 4 terminals especially since the bus bar strips inside the ZW have a tendency to pop off those posts often as they get older & moved around. It's a good redundancy move on any Z, V, ZW, or VW.

JohnGaltLine posted:

A

That's exactly what the ZW meter will do when you use just one "U" connection.

zigzag930 posted:

Perfect!  Exactly as I was envisioning the connections.  

One question John.  Why do I have to use a heavy gauge wire to connect all the U terminals together?  I thought they were internally connected.   My current setup has all the track commons connected at a buss bar and only one heavy wire running to a single U post.   I didn't jumper the U posts as I didn't think it was necessary.

J

As Rob noted, the buss inside a ZW can become loose and not provide a good connection to each terminal.  Also, remember that that one common wire is handling the entire current draw for the four hot posts.  If you're using 12 gauge wire anyway, that can handle the entire output of the ZW, you won't have a problem, but if you're using 16 or 18 gauge it will put a limit on things.  

Can anyone tell me where I can get these meters at?Nick

Got it.  Thanks to everyone for such great (and fast) assistance.  

I will order (4) 20VAC voltmeters and one 15amp AC ammeter to try this out.  Some inexpensive retro round gauges on eBay and Amazon.  Wish they were backlit, but unfortunately not.

 Oh well, should be fun project if nothing else.

J

Nick:  

If you are looking for separate meters, I was considering:

http://www.ebay.com/itm/181311593833

and

http://www.ebay.com/itm/172435642847

Hope that helps.  

zigzag930 posted:

Nick:  

If you are looking for separate meters, I was considering:

http://www.ebay.com/itm/181311593833

and

http://www.ebay.com/itm/172435642847

Hope that helps.  

Zig any idea if these meters have lites in them?Thanks for your help.Nick

No lights.  I wish they did, but at that price, probably not happening.

These are what I use:   https://www.amazon.com/uxcell%...cell+ac+panel+meters

and this one:   https://www.amazon.com/85L1-V-...oltage/dp/B007Q9VW4Q

Get you a small project box and start cutting holes...

Marty