1st Gen Lunchtable Thread - General Discussion

@BartMaster1234, do you have any more specs for that 0-100A ammeter, or a link to it on ebay? Meters like the GE one typically use precision shunts, and the shunts they use have a current rating and a millivolt rating such as "100A, 100 mV" or "100A, 200 mV". The shunt is basically a very low resistance and it converts the 0-100 Amp current to a millivolt signal that connects the two shunt posts to the meter . Precision shunts are quite pricey, you can get cheaper ones, but you have to know the mV your meter requires for its 0-100A range. One things for certain, you need a 100 AMP shunt for that GE ammeter, not a milliamp shunt. If you had test equipment that could provide a milivolt signal, you could test to find out how many millivolts it takes to drive the meter full scale, that would be your millivolt value.

And if you use an external shunt, you have to make sure its well insulated on the mounting base and protected from a short (enclosed in a housing) or you're going to have a bad day.

FYI, I did see on ebay some cheap automotive range digital meters with shunts provided for the current and voltage measurement as well, i don't know how trustworthy those are.

 

Hey! Here is a link to the meter. These gauges are oooold, so I couldn't find anything when I googled any of the numbers on it.

https://www.ebay.com/itm/GE-DC-Amperes-0-100-Shunt-External-Type-DO-91-Panel-Meter/273660384487

This is the shunt I was hoping on using:

https://www.ebay.com/itm/100-Amp-Sh...-Shunt-Screw-and-Bolt-Connection/271914952205

 

That's the dude right there local to you right? I just sent it to my pops too. He'll go nuts as well lolol

 

@davidstacoma

This is my second choice, but I couldn't find a matching vDC meter so I went for the other style. This one comes with a shunt, it's rated for 100A 50mV.

https://www.ebay.com/itm/General-El...0-DC-Amperes-With-External-Shunt/264745892150

 

Yessir. I actually met him last year and didn’t even know it was him. Super cool guy and knows how to catch some big kitties

 

I remember a few years ago, the dude playing the harmonica was playing at some of the bars in the River Market district.

They like to give it a little nawlins theme..

 

I’d love to spend a night around that crowd.

 

New fire road to check out tomorrow; follows the faint red line I drew

 

This kid goes crazy for chewing on beer cans, I'm both impressed and concerned



Have to keep my thumb over the opening lol.

 

If you are ever over this way, just let me know.

 

Shit man I will. I will admit now that if it does ever happen, I will be more then a handful LOL

 

Some of those older style GE ammeters appear to use 50mV, 100mV or 200mV 100A shunts, so I wouldn't count on those shunts being the right. The ebay site you linked to for your meter I did find this information:
GE DC Amperes 0-100 Shunt External
Type DO-91
50-162121ECDK2
AA-12

I Googled the part number 50-162121ECDK2 but could not find this model (its an old GE meter). I did find a GE 50 millivolt meter with the part number NOS NIB 50-162121, which makes me suspect that the "50-" MIGHT mean a 50mV meter for your 0-100A DC ammeter, but I just can't assure you of that:
https://www.ebay.com/i/184324318742...MI_LDVspvd6gIVGey1Ch2hrAaGEAQYAiABEgIhCvD_BwE

Do you know a technician who might have access to a mV signal generator who could test your meter?

 

I couldn't find anything specific for that meter, but these are also GE, and suggests that what you need to know might be stamped on the meter. It also gives wiring examples.
https://docs.natlswgr.com/docs/W1000093.pdf

 

I can see a sequel to The Hangover stemming from this

 

Wow, that's really cool. Thanks for finding that.

Fingers crossed I can get that one to work, I really like the look of those old GE gauges.

 

Edit: That's close, but his is a D0-91 series, do you have a cut sheet for that one? But you might be right, the mV rating could be stamped on the meter body somewhere.

 

Man I would be all over the place lol

 

Old mechanical meters are sweet.

Just be careful with the voltage vs current thing. The mechanical movements I've used in the past operate on current, and if you just put a straight voltage across them you'll burn them up.

And if you run out of luck with GE, simpsons are also sweet:
https://www.ebay.com/sch/i.html?_fr...Desc=0&_osacat=0&_odkw=simpson+electric+meter

 

Those meters do require a mA current to drive them, the shunt applies a mV voltage to the meter, and based on the meter winding resistance, a mA current will flow through the winding. For example for a 100A DC ammeter requiring a 50 mV shunt, a 10 ohm meter winding resistance with 50 mV applied would cause 5 mA to flow to make the meter go full scale (I=V/R).

 

This would be Miguel