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12V test light

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finn

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Does any one make a 12V incandescent 1 amp test light ?
Probably not incandescent, but there are dozens of low draw led test lights claimed to be suitable for ecm work listed on the Jungle site for $20-25.

Don’t know what the actual draw is, though.

Would a Power Probe work for you?
 

APEowner

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Sunny, New Mexico
If you need to limit your current draw to 1 amp then I don't think an incandescent test light is the correct tool. What is it that you're trying to accomplish?
 

Steve W.

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An incandescent bulb that draws one amp will be PLENTY bright. A standard 1157 tail/brake bulb is two or three WATTS on the tail filament, that is only about 1/4 amp. The brake filament is about 30 watts, which is about 2.5 amps.

I have never seen a request for a test light with a specific draw. What is your application?

.
 

2ndGearRubber

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That won't be that common.

A typical 168 bulb is 1/4amp, a 7440 tail lamp bulb is about two. Most off the shelf test lamps that one can buy are 1/4 to 1/2 amp.
 

dnschmidt

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Here was my solution to the test light doesn't draw enough amperage test lite to force a voltage drop problem. Find a high wattage bulb of the same size and shape as the bulb that comes with the cheap Harbor Freight test light and substitute it for the low wattage <200 mA bulb that comes standard in the HF light. Only issue is that this bulb gets hot enough if left on long enough to melt the plastic of the test light. So momentary usage only. If all is well, and there is no high resistance issue, that sucker is about a bright as arc welding.
 
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T

theoldwizard1

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Probably not incandescent, but there are dozens of low draw led test lights claimed to be suitable for ecm work listed on the Jungle site for $20-25.

Don’t know what the actual draw is, though.

Would a Power Probe work for you?
You are missing the whole point ! I want a test light with a HIGH (1A) current draw !
 
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T

theoldwizard1

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Find a high wattage bulb of the same size and shape as the bulb that comes with the cheap Harbor Freight test light and substitute it for the low wattage <200 mA bulb that comes standard in the HF light.
I have spent HOURS searching for a festoon base bulb that is greater than 15W (a bit more than 1A @ 12V). I haven't found one yet.
 

Radio Flyer

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not sure it it helps…..

I had a coworker that would put an old school dome light bulb in his test light for just that purpose.

mostly used on pesky trailer connections/ lights.

Kinda like this.FullSizeRender.jpeg
 

RTM

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If you can’t find one, I’d look for a new probe that uses a different bulb, I can find 1.25a bulbs, 10w bulbs, etc. that skirt around what you want.
 

four.cycle

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back in the day...
when they printed paper catalogs, Westinghouse, Sylvania, and other bulb manufacturers all printed a chart which included ALL the bulbs they made from little "grain of wheat" stuff up to big halide bulbs for football stadiums.
specifications were all listed - you could find what you wanted by BASE, voltage, watts - not sure if they mentioned AMPS.
might see if you can get your eyeballs on one of those.
 
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Steve W.

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When testing 12V (automotive) things, it is important to know that not only you have voltage at the load (test point), but also CURRENT !
I like to at least verify voltage first, so a VERY low-current LED test light is very adequate. Once I verify voltage, if the load is not active, I at least know that the problem is downstream of the test point. Not sure that drawing a one-amp load would tell you much more.

Besides a light, there is not much that is only going to draw a single amp. :dunno:

.
 

bwringer

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When I want to load test something I use test leads and a headlight bulb.
Closer to 5 amps, but there are smaller bulbs available.

Me too.

But I have wished for the following before a few times, to no avail. I think if this existed, the GJ Hive Mind would know about it already.

I would like to have a small box.

The box will have two attachments for standard test leads and a dial.

The dial will be marked in various amperages, from, say, .5 amp to 5 amps. Something like that.

The box will also contain a squeaker speaker and a light source, both of which are switchable.

When switched on, the squeaker will make some sort of noise, with volume and/or tone in accordance with the current range, and the light will do the same, so that one may develop some understanding of the current being passed without needing to look directly at the box from close range.

The box doesn't really even need a display of any kind; I already have meters for all that.

Basically, I want a variable load box for testing circuits under load, with the ability to squawk and/or make a glow if I want.

So far, like many others, I have made do with a homemade assortment of scavenged automotive light bulbs and sockets.

And no, I am not talking about a Power Probe; that could be regarded as a related tool, and could certainly be used in conjunction with this variable load box, but it doesn't have a variable load function.
 

2ndGearRubber

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You are missing the whole point ! I want a test light with a HIGH (1A) current draw !

You want a sealed beam headlight, around 4.5 amps. My main voltage drop bulb is a 2amp unit.

For those who don't understand why you need a load - you load a circuit then check for voltage drop on the power and the ground. An LED test lamp or meter can show voltage, but not ability to flow current. I can have a rotten starter wire that has a single strand of good copper. It'll show B+ all day long, but won't illuminate a 4.5 amp lamp. This is also why resistance testing is no good for testing ability of a wire to supply a load. That rotten cable will show B+ at the starter, but that rotten cable will never supply a 500amp inrush current.
 

2ndGearRubber

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Me too.

But I have wished for the following before a few times, to no avail. I think if this existed, the GJ Hive Mind would know about it already.

I would like to have a small box.

The box will have two attachments for standard test leads and a dial.

The dial will be marked in various amperages, from, say, .5 amp to 5 amps. Something like that.

The box will also contain a squeaker speaker and a light source, both of which are switchable.

When switched on, the squeaker will make some sort of noise, with volume and/or tone in accordance with the current range, and the light will do the same, so that one may develop some understanding of the current being passed without needing to look directly at the box from close range.

The box doesn't really even need a display of any kind; I already have meters for all that.

Basically, I want a variable load box for testing circuits under load, with the ability to squawk and/or make a glow if I want.

So far, like many others, I have made do with a homemade assortment of scavenged automotive light bulbs and sockets.

And no, I am not talking about a Power Probe; that could be regarded as a related tool, and could certainly be used in conjunction with this variable load box, but it doesn't have a variable load function.

I solder stacking banana jacks on old tail lamp wiring. Makes for instantly installable test lights of whatever load I like.
 

charbar

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You DO or DO NOT want a festoon base bulb? Couple of your post confused me on what style of bulb you are looking for.

18 watt ones here..... https://www.ebay.com/itm/3344447718...80153139072974&abcId=9300907&merchantid=51291

Comes from the UK though, Im sure someone else in the states would have them though.


18 watts at 12 volt is 1.5 amp, or 1.28 amp at 14 volts...... Exactly how close to 1 amp do you need to be?


Im like 2ndGearRubber, I just have multiple automotive bulbs with sockets and their current draw written on them.
 

signcrafter

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May 9, 2012
Messages
12,365
Buy a loadpro for you dmm. Problem solved. Or if cheap buy a resistor to put inline with your test light. many ways to accomplish what you want.
 

2ndGearRubber

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Buy a loadpro for you dmm. Problem solved. Or if cheap buy a resistor to put inline with your test light. many ways to accomplish what you want.

Problem with the load pro is its hard to connect into a circuit, and there's no visual confirmation of success. My load pro had a threaded end, for spin on connections like alligator clips. It'd be much easier to use with a banana jack on the end.


The problem with product like the OP and others want is the target audience. The target needs to both understand current flow AND have a need to test it via voltage drop with a load. That's a very small % of even the technician market. Sure an electrical engineer understands voltage drop, but are they actually doing their own testing? This then leads to the target market mainly being technicians. However techs have access to make their own equipment, further limiting market share. I have a half dozen test lamps, plenty to not need any other products.

I don't buy anything but the stacking banana jacks to solder on. When I replaced tail lamp assemblies I just cut out the pigtails.
 

RTM

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I like to at least verify voltage first, so a VERY low-current LED test light is very adequate. Once I verify voltage, if the load is not active, I at least know that the problem is downstream of the test point. Not sure that drawing a one-amp load would tell you much more.
Back in the day (80s), when I used to upgrade PLCs, we had a problem with voltage leakage. Low current draw loads weren’t enough to switch the output transistors on the new output cards, and the bulbs would glow dimly with the outputs off. A volt meter would show voltage, even with the output off.

Similar problems with trailer lights back in the day, the VOM would show voltage, but a lightbulb would not light. Keep my vintage idiot lights to show the wannabe EEs in the crowd how to test.
 
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Steve_P

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6B90BAF5-22EB-49AD-88D2-5795E7A0E2C4.jpeg
I build my own. A #105 bulb will draw 1 amp at 12 volts.
I make them up with clips, pins and banana jacks.

I like those a lot. Very nice. Do you have a PN and source for those sockets? I ask because they look new, so I'm guessing you bought them for this purpose.

I looked for a 1A light, like the OP is looking for, a few years ago and found nothing. I ended up getting a ~0.5A light, I think it's an OTC. It's ok, and the price was reasonable, but the alligator clip was junk and I immediately replaced it.
 

Steve_P

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Sep 15, 2010
Messages
5,185
Me too.

But I have wished for the following before a few times, to no avail. I think if this existed, the GJ Hive Mind would know about it already.

I would like to have a small box.

The box will have two attachments for standard test leads and a dial.

The dial will be marked in various amperages, from, say, .5 amp to 5 amps. Something like that.

The box will also contain a squeaker speaker and a light source, both of which are switchable.

When switched on, the squeaker will make some sort of noise, with volume and/or tone in accordance with the current range, and the light will do the same, so that one may develop some understanding of the current being passed without needing to look directly at the box from close range.

The box doesn't really even need a display of any kind; I already have meters for all that.

Basically, I want a variable load box for testing circuits under load, with the ability to squawk and/or make a glow if I want.

So far, like many others, I have made do with a homemade assortment of scavenged automotive light bulbs and sockets.

And no, I am not talking about a Power Probe; that could be regarded as a related tool, and could certainly be used in conjunction with this variable load box, but it doesn't have a variable load function.


Hurry up and send this idea to Lisle, before someone else here does :LOL:
 

Buster21

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Aug 16, 2014
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418
Location
Idaho
I like those a lot. Very nice. Do you have a PN and source for those sockets? I ask because they look new, so I'm guessing you bought them for this purpose.

I looked for a 1A light, like the OP is looking for, a few years ago and found nothing. I ended up getting a ~0.5A light, I think it's an OTC. It's ok, and the price was reasonable, but the alligator clip was junk and I immediately replaced it.

I know I got them from Amazon, I think a four pack. It's a BA15s base which is the same as 1156 bulb which is more common.
 

Steve_P

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Messages
5,185
I know I got them from Amazon, I think a four pack. It's a BA15s base which is the same as 1156 bulb which is more common.

Thanks! I looked on Amazon and they have all sorts of 1156 and 1157 sockets.
 

johninct

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Dec 21, 2010
Messages
2,596
I had a test light that had a real bulb in it like 25 years ago. I misplaced it when the bulb went bad and would really like another one. It was very simple and quick to use like a regular test light of today. Hook it up and look at the light. If the bulb burned dimmer than usual connect the ground to a known good ground. If it was still dim, then the positive wire is probably bad.
 

kbeefy

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Sep 14, 2013
Messages
3,453
Location
Harington, Eastern Washington
Me too.

But I have wished for the following before a few times, to no avail. I think if this existed, the GJ Hive Mind would know about it already.

I would like to have a small box.

The box will have two attachments for standard test leads and a dial.

The dial will be marked in various amperages, from, say, .5 amp to 5 amps. Something like that.

The box will also contain a squeaker speaker and a light source, both of which are switchable.

When switched on, the squeaker will make some sort of noise, with volume and/or tone in accordance with the current range, and the light will do the same, so that one may develop some understanding of the current being passed without needing to look directly at the box from close range.

The box doesn't really even need a display of any kind; I already have meters for all that.

Basically, I want a variable load box for testing circuits under load, with the ability to squawk and/or make a glow if I want.

So far, like many others, I have made do with a homemade assortment of scavenged automotive light bulbs and sockets.

And no, I am not talking about a Power Probe; that could be regarded as a related tool, and could certainly be used in conjunction with this variable load box, but it doesn't have a variable load function.

I think that would be fairly easy to build with a project box and a few parts.
A variable potentiameter would do the trick, current would vary with voltage and resistance setting.
If you wanted to be really fancy it could include a shunt and an ammeter as well.

I like a speaker and a light for remote monitoring. Some of my test equipment now has bluetooth/wireless monitoring which is nice, but adds an extra set of batteries to maintain.
 
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