Skip to main content

Earlier in this thread I had reported purchasing digital AC ammeters with very small gauge wires.  I looked back on my eBay purchases hoping to find those but no luck. I did not keep those very long.  What I am using NOW are as shown in the attachment to this email.  The shunt is INTERNAL and the screw terminals can accommodate wires of reasonable size--I use #16.  This one has a blue background LCD display and sold for $11 each in early 2019, from vendor elite.element.  All AC ammeters must have a shunt, but some, like this one, has it internally.  Voltmeters do not use shunts.  An external shunt would be better in that a high current incident that results in a burnout would only damage the external shunt, at least theoretically.AC 0-10A Digital Amp Current Panel from elite.element

Attachments

Images (1)
  • AC 0-10A Digital Amp Current Panel from elite.element
superwarp1 posted:

Here’s the first video...

I won't tell your boss... but is there any way to sneak in an engine to your office?

That is, I see you were comparing the readings to a bench meter with a resistive load.  But modern engines using DC motors present a non-resistive load.  So even if you apply a pure sine voltage, the current will be anything but.  It's kind of, sort of, like the chopped-sine voltage measurement problem where a basic AC voltage meter will under-report the voltage...and guys have even created conversion table cheat-sheets or whatever.

Likewise, a basic AC ammeter will also under-report the current if driving a non-resistive load.  And, again, I suppose one could come up with a cheat-sheet conversion table.  I'm imagining a discussion where some 10 Amp breaker keeps tripping even though the meter reads something less than 10 Amps.  I guess it depends on what the objective is.

 

Gunrunnerjohn

My friend gippers alerted me to your post.

I've been looking forever, for readable, AC digital volt & amp meters in the 18V & 1-3 A range. Thanks for your knowable to the point discussion, and finding these gems. Since you could select the current i assumed there was a shunt present (but couldn't find in spec's) and those small gauge wires didn't give me a warm feeling. I've wondered about isolation as well. you've answered all the questions.

One thought:    I plan to install the meters on the INPUT side of the DCS- TIU to eliminate the possible corruption of the track's digital communication signal.

Second:    1 meter { VOLT or AMP } could easily be used for 2 Tracks with a double pole double throw 10 A bat handle toggle switch or a pair of meters, 1amp, 1volt could be used for 2 Tracks with 4 pole relays.

Third:    From "AutomationDirect" ice cube relays with 12-vac or 12-vdc coils W/ 15amp contacts and sockets available for convent wiring and mounting. they come with a manual activation lever and pilot light. The AC-volt coil cubes are { search on there site for- 781 = single pole, thru 782, 783, 784 = four pole } all for a reasonable price. Single pole $4.75 & Four pole $8.00. 

Thanks again    

Add Reply

Post

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
Link copied to your clipboard.
×
×