Hello everyone! I have just recieved my (Amp0-15) and (Volt0-30) gauges from Lightobject.com, but I have some questions about wiring them up. My layout power is being provided by four Lionel 180w powerhouses. I purchased one amp/volt gauge for each brick. Witch gauge should be wired first in the series? And does the amp gauge need a shunt? or is this only for DC applications?
Thanks for all your help!
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Assuming you bought AC meters, the Voltmeter is easy, just wire across red and black. Parallel to transformer.
The Ammeter may need a shunt(may be included), and is inserted in the RED wire between transformer and center rail. In series with red wire.
Ed
Yes, they are AC. Volt meter is pretty straight forward! Concerning the Amp meter, connect one end of meter terminal to the positive side of transformer, and connect the other terminal to wire going out to center rail? should the volt meter be wired across after it goes through amp meter or before?
It doesn't matter where the voltmeter is connected, the ammeter should be basically a short. If it has a shunt, make SURE that is in place or the meter will die as soon as you draw any power through it!
John, excuse me but what is a short?
"short" AKA a wire. It means that the ammeter will look like a wire connection between it's terminals, it's pretty much a short circuit as far as the current is concerned.
Got it! Thank you all!
Jerry(and anyone else): an ammeter is actually a voltmeter--but it's only measuring the minute voltage present across the shunt, which may be internal(inside the meter) or external-- external shunts are usually used for high(> 20-30 amps) currents and look like a piece of copper bar of a specific length and width and thickness. They are usually stamped with the conversion factor(typical 50 millivolts per amp). Internal shunts are just a piece of wire--
Yeah, I dont know if this one has a built in shunt or not. I got it from lightobject.com & the item # is EPM-AAC15A. It doesnt say anything about it in the item description. I really dont even need them. I just thought it would be cool to monitor real time voltage & amperage on each block. I will build a nice box to mount the meters on and wire everything up. then I will post some pictures.
Well that is if I can figure out how to upload saved pics from my samsung tablet! I tried to do it earlier, but everytime I try to add an attachment it takes me to some weird black screen stating there are no files to download???????? But thats a whole different thread topic.
Fargus
If I can get it scanned the photo below of color-coded wiring for the rear of a 3 power district AC meter panel may help. Top row: Volt meters, Bottom row: Amp Meters. These are DER 670 meters but Light Object brand functions the same. No shunt involved.
Color Code:
-White is common.
-Hot wires: Black=district #1, Red=district #2 and Green is #3.
The colored hot wires are inbound from a transformer hot post[via a T-strip] to the left post of the Amp Meter and from the right post the wire run is back via a T-strip outbound to the track center rail. This is described as wired "inline", or "in series", and is the direct "short" gunrunnerjohn mentioned.
Power on the hot wire flows directly through the Amp Meter[the common is not involved on the Amp Meter]. The entire load of the power district is flowing through the Amp Meter, so the same heavy wire used in the railpower district wire runs should be connected to the meter.
Volt Meter: Note that short colored jumpers are connected from the hot post[inbound] of the Amp Meters to the left post of the Volt Meters. The white common from the transformer [via the T-strip] is connected to the right hand post of the Volt Meter and short white jumpers are extended to the right hand common posts of the other two meters. This is described a being wired "across the line" or "in parallel". The common wire run is connected to the outer rail.
Second photo shows the layouts distribution terminal strip which organizes and distributes all railpower, including the meters that monitor it.
Hope this helps.
Here you go...
Way to go Rich, even I can undestand that! 
Doesn't get any plainer than the illustration. KISS!
SWEEEEEEEEET!!!!!!!!!! Thanks to all, for all your help!
Thanks Rich. I needed this and doesn't get any easier than your drawing.
On a related note, I have some Lionel 1.8 amp transformers that don't designate between the A and U connections. Is there a right way to find out to hook up a volt and amp meter? Thank you, Terry
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