12V to 6V for voltmeter

B-O-B

Well-known member
Will a volt meter designed to operate on 12V, if you use a voltage reducer to 6V work properly? I can purchase a S W 12 V battery voltmeter but I want to put it in my 34 roadster still on 6 volts.
Thanks;
B-O-B
 
Will a volt meter designed to operate on 12V, if you use a voltage reducer to 6V work properly? I can purchase a S W 12 V battery voltmeter but I want to put it in my 34 roadster still on 6 volts.
Thanks;
B-O-B

Yes is should work. The meter will read 12 volt full scale. Meaning it
should move all the way to the right when it is looking at 12 volts. I
wouldn't use any resister, what you see on the meter is the voltage
you have. If you charge the battery you need a meter that reads 15
or 16 volts. G.M.
 
Voltage reducer wouldn´t do you any good in this case.
A 12v voltmeter usually starts at a voltage to low to really be any good in a 6v system.
If the voltmeter starts at 7v it will barely show any movement until rpm is up and generator charging.
Anything can be rebuilt and converted...but it´s probably less of a pain and cost to keep searching.
 
There was a thread on here a month or two ago, and IIRC, someone found a source for a decent voltmeter to be used for a 6 volt system. A "Search" should find the thread.
 
Guys thanks very much.
I need to find something that would work on S W wings series gauges. What I have is a 21/6" 3 hole mounting panel & have water & oil. I would like to find some wings 6V gauge to fill the hole.
search comes up with O
 
Analog voltmeters aren't 12 volt or 6 volt. They will work on any voltage up to full scale. Now if full scale is 50 volts, you won't be able to tell 5 volts from 7 volts. If full scale is 15 volts, it may be possible. You really want full scale to exceed the maximum charge of your generator and to survive the maximum discharge of your battery through the voltmeter.
 
Analog voltmeters aren't 12 volt or 6 volt. They will work on any voltage up to full scale. Now if full scale is 50 volts, you won't be able to tell 5 volts from 7 volts. If full scale is 15 volts, it may be possible. You really want full scale to exceed the maximum charge of your generator and to survive the maximum discharge of your battery through the voltmeter.

Most voltmeters for use in cars don´t start on 0...they have a narrow span close to working voltage to be accurate...So with a 12v unit starting on 7v using it on 6v will be difficult.
 
There was a thread on here a month or two ago, and IIRC, someone found a source for a decent voltmeter to be used for a 6 volt system. A "Search" should find the thread.


This is likely the thread that tubman is referring to above.....click on the link below! It's not exactly the answer you want, but the info therein may give you a better understanding of the realities of situation you're dealing with. If you're determined to keep the look of the "WINGS" gauge, you may have to consider gutting a used 6v gauge and somehow refitting the movement in your WINGS case, along with some creative, custom artwork for the faceplate. Just depends on how important it is to ya to "think" you're foolin' the guys that are in the know. And the REST of the folks don't really matter 'cuz they ain't got a clue anyway! In reality, you're probably going to an awful lot of trouble and expense that ain't gonna impress anyone but YOU! If someone doesn't like your gauge, tell 'em to KISS-OFF! Link below! DD


https://www.fordbarn.com/forum/showthread.php?t=275920&highlight=voltmeter


volt1.jpg



……..
 
I would take & use a vacuum gauge in the wings 2 1/16" series. I will keepon keeping on looking.Some one has to have one that they are not using & willing to sell.
I don't plan to spend a ton of money for one,it is not that important.
Coop I'm just trying to build this car for me & I could care less what others have to say. Like they say"My car My money". I could use the two gauge panel that I have but like the 3 gauge panel better. I have this one now.
 

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B-O-B
Since the 12 volt SW wings voltmeter scale reads from 10 to 16 volts. There is a way to still use the 12 volt SW gauge. By adding a DC to DC Boost Buck Converter Step Down Up Regulated Power Module you could feed this regulator with the cars 6 volt output and then adjust the regulated power module so the output feed will be 12 volts. Now when the car is running the 6 volts will show 12 volt on the gauge When you see the reading is 12 volt you know the car is charging. These regulated power supply's are easy to find on Ebay and most of them are less than $20.00 with free shipping.
Ronnieroadster
 
B-O-B
Since the 12 volt SW wings voltmeter scale reads from 10 to 16 volts. There is a way to still use the 12 volt SW gauge. By adding a DC to DC Boost Buck Converter Step Down Up Regulated Power Module you could feed this regulator with the cars 6 volt output and then adjust the regulated power module so the output feed will be 12 volts. Now when the car is running the 6 volts will show 12 volt on the gauge When you see the reading is 12 volt you know the car is charging. These regulated power supply's are easy to find on Ebay and most of them are less than $20.00 with free shipping.
Ronnieroadster

Please educate me on how that will work ??
A step up or step down regulator have a fixed output voltage...not like it is proportional to the input...
 
Please educate me on how that will work ??
A step up or step down regulator have a fixed output voltage...not like it is proportional to the input...




It works like I wrote feed in 6 volts it will output where you set it you want the 12 volt out put thats what you get. There ADJUSTABLE for desired setting pretty easy to understand.
 
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It works like I wrote feed in 6 volts it ill output where you set it you want the 12 volt out put thats what you get. There ADJUSTABLE for desired setting pretty easy to understand.

Ok so you will have it show 12v all the time...that´s as exciting as painting a needle on it with a crayon :D
Thought you had found some way of actually making them show what was going on with the 6v charging system...

A simple squarewave from a 555 timer and a voltage doubler would give you a 12v signal proportional to the 6v input...that way you should be reading double the voltage you have.
 
Ok so you will have it show 12v all the time...that´s as exciting as painting a needle on it with a crayon :D
Thought you had found some way of actually making them show what was going on with the 6v charging system...

A simple squarewave from a 555 timer and a voltage doubler would give you a 12v signal proportional to the 6v input...that way you should be reading double the voltage you have.

Well the way I see and how this works if the 6 volt changing system is not working to that voltage output then the reading on the SW gauge will go lower since it will read down to 10 volts. Thus showing whats going on with the charging system voltage rather simple to understand the reading on the SW voltage gauge.
How you determine a crayon and excitement can be related to the post is amusing for sure. Heck its possible not using the original amp gauge for a charge reading may also add economy to the equation.
 
Well the way I see and how this works if the 6 volt changing system is not working to that voltage output then the reading on the SW gauge will go lower since it will read down to 10 volts. Thus showing whats going on with the charging system voltage rather simple to understand the reading on the SW voltage gauge.
How you determine a crayon and excitement can be related to the post is amusing for sure. Heck its possible not using the original amp gauge for a charge reading may also add economy to the equation.

DC-DC converters work in the way that a wide span of input voltage...lets say 6-15 gives you the same stabilized 12v output so as soon as you turn on the ignition the gauge will show 12v volt charging or not.

For the meter to show anything else then the set 12v...input has to go below the units minimum operating voltage and then output will be 0.

The car will probably stop running from low battery voltage before the regulator drop out voltage is reached and gauge wiill show a difference.
 
I already have a DROK step up 6V to 12V unit bit it is used for my third brake light. I wouldn't to over burden it. I guess that I could give DROK a shout out if they are still working. The light is from a suburban. Works great for the last 3-4 years.
 

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There are meter repair companies all over the country that can convert expanded scale voltmeters to read normal zero. They can duplicate scales to look like anything.
You can have anything you want for a price.
 
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