I would like to hook an ammeter to a loop of track that is powered by a postwar ZW, and I was wondering what type of ammeter I need, and how to hook it up. I appreciate any suggestions.............
Barry Franklin
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There are certainly a wide variety of ammeters out there that you could use. I used the simplest of the bunch - free full range voltage meters from Harbor Freight. I simply wired in the red and blacks leads from the voltage meters to the plus and minus leads to the track. I attached the voltage meters to the end of my layout and set them to the AC setting. I use seven of them. As cheap as you can get, but they work great.
Ron
Ammeters and volt meters are two different things and get wired differently.
Would you like to measure the voltage (pressure) on the track, or the current flowing through the train?
@RON ARNDT 091718 posted:There are certainly a wide variety of ammeters out there that you could use. I used the simplest of the bunch - free full range voltage meters from Harbor Freight. I simply wired in the red and blacks leads from the voltage meters to the plus and minus leads to the track. I attached the voltage meters to the end of my layout and set them to the AC setting. I use seven of them. As cheap as you can get, but they work great.
Ron
Where do you put them all?
John
@Barry Franklin posted:I would like to hook an ammeter to a loop of track that is powered by a postwar ZW, and I was wondering what type of ammeter I need, and how to hook it up. I appreciate any suggestions.............
Barry Franklin
You can get them cheap on the Shhhh! place.
John
Deleted my careless comment
As a retired electrical engineer, RadioRoy is absolutely correct. If wired as previously stated, both meters will be fried.
@RoyBoy posted:Absolutely not! They are wired exactly opposite of that.
Proofreading is always a good thing.
YIKES
I can't believe I did that. So sorry. Deleted. First time using phone to post. No excuse though
John
Barry,
One terminal of an RMS-reading AC ammeter is connected to terminal "A" on the ZW while the other terminal of the ammeter is connected to the center rail. (Ideally, there should be a circuit-breaker connected to terminal "A" with the ammeter then connected to the circuit breaker.)
The argument among engineers/electricians is whether the ammeter should be an analog meter with a needle or a digital type with a numerical display. Both types will correctly read amperage. I personally find the old-fashioned analog meters easier to read and interpret but I see that my classic Simpson panel meters now sell for $100 each. So you may just want to make your decision based on cost.
eBay: 193649193137
AC Analog Ammeter Panel Mount 0-10 Amp AC PM0010-AC
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Thanks to everybody who commented on this. I appreciate it.
Barry
Gunrunner illustrates a practical, affordable 0-10 range analog meter that can be used for each 10 amp power district.
The photo above shows the rear of a meter panel for 3 power districts--red, green, black hot wires and white common.
Bottom row are the AAC ammeters wired inline with the heavier gauge wire which has capacity for a 10 amp load, note the power enters one side of the meter and returns from the other for an in-line amperage reading.
The 25VAC volt meters mounted top row are energized via a short colored small gauge jumper from the hot side of each ammeter up to each volt meter connecting on one side and the common on the other to complete the across-the-line voltage reading.
Below -- front of a panel (not the same) as panel illustrated below with the two VAC meters showing 18 volts. The black boxes are Power Guards that were an early expensive ($85), design to arrest voltage spikes , a job now performed by a $.50 cent item. On the right is a VDC meter showing 12 volts a for the 17 Tortoise switch machines..
February 2010 photos
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