The e-matches have the following: Fire current: .37A Test Current 0.5MA

That's a problem.

.5ma isn't going to give much of an indication (brightness) from led.

This sight shows 200ma as maximum no-fire current. Two brands.
http://www.pyromate.com/Basics-of-Electrical-Firing.htm

Quite a difference.

 

That's a problem.

.5ma isn't going to give much of an indication (brightness) from led.

This sight shows 200ma as maximum no-fire current. Two brands.
http://www.pyromate.com/Basics-of-Electrical-Firing.htm

Quite a difference.

Yea well I already have the e-matches and the ones I have are readilly available.

I'm thinking the circuit that lights the LED's will have to be seperated from the circuit that is sending the test and fire currents to the ematches.

 

I guess that also brings up the question on what if in the future the ematch has to change and the test and fire current changes. Sure take it apart and change that part out of the circuit but it would be better if I could adjust it some how. Starting to think this is getting really complicated now which maybe explains why they sell these things for $1000+

 

I question the .5ma. Is this a new type electronic match?

Try .5ma thru you led. See if you can live with the brightness.

 

My DC Bench power supply won't ship until next week and will probably take a week to get here. I do know the LED's lit using continuity check using my Fluke meter which surprised me.

I'll have to use some batteries and a resistor to see what it looks like at .5ma

 

Leds I tried need over 1ma.

I'd like to use 10+ma.

 

The sample buttons I received I told them 12v and they preinstalled a resistor on one of the LED legs. It's SUPER tiny I'll have to find a magnifing glass to tell what color bands it has.

 

The sample buttons I received I told them 12v and they preinstalled a resistor on one of the LED legs. It's SUPER tiny I'll have to find a magnifing glass to tell what color bands it has.

Not important. You can measure the current.
The internal resistor is R2 in my last diagram.

.37 amp is 370ma.
1/10 of that is 37 ma. It's hard to imagine 37ma or 1/100 @ 3.7 ma not being safe.

I'll research it but you will have to decide.

Each fire circuit will need an amplifier if limit is .5ma.

Anyone else have an opinion?

Edit:

Found this:
NEVER USE A MULTIMETER TO CONTINUITY CHECK AN ELECTRIC MATCH
They send too much voltage and will set off the match. A true tester is insured to only use .1ma - .5ma I believe

 

That's good to know but even if I had done that (which I haven't) that would be something I would of done outside for safety reasons. I will be wearing safety glasses and be outside anytime an ematch or firework is in play. That's why I was thinking I need to build an LED circuit that resembles what the ematch's current is the .37A and .5MA

This will be my lack of knowledge here but my thinking was if I'm sending whatever the MAX current needed is lets say 1A and it's going through a switch to either the test fire current leg of the circuit (green) or fire current leg of the circuit (red) that on each of those leg's there would be resistors to the ematch on the test leg one to limit to .5ma or less and on the fire leg could let all of it through or limit to .37A or higher but to the LED's on both legs of the circuit resistors for those which currently are being installed by the supplier of the button.

Forgive me if I'm totally not getting electronics here but I thought I read the current flows through the path of least resitance so more current would go to the LED's vs going to the ematch.

 

True, but if the current isn't going thru the ematch, it's not testing it. Enough current would go thru the bypass to light led. Even if the ematch wasn't in circuit.

Draw it up. I'll take a look.

To test, the whole .5ma must be needed to light led.

I don't see another way.

I have some ttl indicator lights. Don't know if they are still made.
Wouldn't be built into your switch though.

I'm hoping someone will step in with a simple fet circuit that works with my diagram.

If not I'll have to go with bjt transistor amplifiers.

 

Couldn't the power to the button be at the current for the LED and the resistor be from the LED to the ematch and back or does that not work so that a higher current goes to the button led and is limited to the ematch. Again my lack of experience here maybe at play.

 

Or what if the current was split and a transistor was used and the loop of the ematch at the test current rate causes the transistor to allow the higher current to the green led.

 

Just looking at the test circuit for now.

Current must go thru match to test it.

Current must be limited to .5ma.

.5ma will not light led.

Some of the current could be bypassed around match, but it would have to be 90%.

The 10% going thru match will not show much difference in led.

 

Or what if the current was split and a transistor was used and the loop of the ematch at the test current rate causes the transistor to allow the higher current to the green led.

This is a start.

It will get quite complex.

There are many ways to do it. No longer a simple method.

 

I think at this point it would be best if I get some of the parts and put them together based on everything we have talked about and actually try it and see what the results are.

For this testing though definitly want to make something that will simulate the ematch as I'll need that to test anyways with actually burning up a bunch of ematches.

 

Pick up a few marker lites. (not led)

Or use 1157 lamps. Takes .5A to light.

 

Pick up a few marker lites. (not led)

Or use 1157 lamps. Takes .5A to light.

This
http://www.grainger.com/product/21U604?gclid=Cj0KEQjwx4yfBRCt2rrAs-P5vtkBEiQAOdFXbXC3SYgI3Xja0Y41VRBnRY_FftIu7loeU_mi3T_fcwgaAqh38P8HAQ&cm_mmc=PPC:GooglePLA-_-Lighting-_-Lamps-_-21U604&ci_src=17588969&ci_sku=21U604&ef_id=U5DHqAAABPxDvXYh:20140807180232:s

Searching for marker lights I came up with a lot of automotive light kits.

 

That works. Have to get sockets or solder on leads.

Don't need the dual filament, but won't hurt.

 

ok should be able to just go to an automotive store for that then.

 

Correct.

This shows the fire circuit.

Is anyone following this?
Do I need a collector diode?
When firing base will go above collector.

How about D1?