Autometer pyro

[jdr2710]

A voltage regulator IC might be the solution, but if you don't like the more complicated electronics you probably won't like it much. They are typically 3 connection devices, but you have to do some additional circuitry to setup the output voltage.

page 8 figure 2 of the pdf below shows what you need to do to set the adjustable voltage:

http://focus.ti.com/lit/ds/symlink/reg1117.pdf

If that doesn't bother you too much we can try to find an IC that will suit you. You would probably want a small project box to put things in, and maybe a perf board circuit board to solder things into so they are nice and neat. Radio shack probably has everything you'd need in stock.

Let me know if you want some help picking out the parts if you want to go with the IC regulator.

Jeff

 

[jdr2710]

I just had time to do a quick search of radio shack. Turns out they have a fixed regulator that would do what you need:

+12V Fixed-Voltage Regulator 7812 - RadioShack.com

For 200mA you shouldn't need to heat sink it, just connect 24V to one leg, ground to another and your gauge to the third. The packaging should show you which leg gets what connection.

 

[Beerslayer]

The Rat Shack voltage regulator looks like a good way to go. I did the same thing as you, bought an Isspro 12v pyro. I contacted Isspro and they sold me a zener diode for a couple of bucks to wire in series with the supply. It works fine.

 

[m16ty]

Picked up a 7812 regulator from my local Radio Shack today. Looks like this is the way to go for less than 1amp loads. It's only about as big as a figernail and cost less than $2.00.

Thanks Jeff.

 

[bond024]

you could go with a 24v to 12v converter

Welcome to 24 Volt DC Products

 

[m16ty]

you could go with a 24v to 12v converter

Welcome to 24 Volt DC Products

But not for $2.00.

 

[bond024]

yea i know, but for $50.00 you can get a 2.5 amp converter which would be enough. He already bought the gauge. The maufacture won't return it for a 24v.

 

[m16ty]

yea i know, but for $50.00 you can get a 2.5 amp converter which would be enough. He already bought the gauge. The maufacture won't return it for a 24v.

I am the guy that bought the gauge .

While the 12/24 converters have their place it's just too much for what I'm wanting to do.

What I was trying to say was a 7812 regulator cost me $2 and will work fine with the gauge so I don't see spending $50 for something that will do the same thing.

You do have a point in that I would have extra power to run other things with the converter but I could buy three 7812 regulators to handle the same load.

 

[bond024]

That will work too. I have been deciding on what route I have been wanting to go too. I am getting ready to add a bunch of 12v items on my truck. I really want to add a 12v alternator and another battery. That will be a summer project.

 

[Beerslayer]

I like the $2 way. Plenty good to run the lights in that gauge.

 

[rchalmers3]

Ty,

What have you decided to do to facilitate the gauge installation?

Rick

 

[m16ty]

Rick, I've bought the Radio Shack 7812 regulator and plan on running the gauge through it. The regulator supplies a constant 12v output (regardless of load).

The only down side is it's only rated for less than one amp load and some say they will overheat at half that (500mA). That's ok with me though because I'm only going to be pulling about 200mA.

I'm going to try and get it installed this weekend if I have time. I'll report how it works.

 

[m16ty]

Finally got the pyro installed today. Built a box that attached to the steering column and houses the pyro and a boost gauge. The 7812 regulator works like a charm. I wired the lights for both gauges in series so they are still on 24v.

I was all set to pull the turbo to drill for the probe but got to looking at it and decided to drill and tap with the turbo in place and the engine running. Worked better than I thought and I'm pretty sure no shavings entered the turbo because of the amount air that was comming out of the hole.

Then I took it for a test drive. I have to get on it pretty good for the boost gauge to show anything. In a good pull my boost maxed out at about 7psi. The EGT jumped up to about 600deg just "putting around" and maxed out at around 900deg under heavy load.

Now to start playing with the smoke screw and see what she'll do.

I'll get some pics of the gauge mount and post them up.

 

[cessnatwin]

buy a digital!

 

[m16ty]

Here's some pics of they pyro and boost gauge mount.

 

[steelandcanvas]

"smoke screw"

Very nice job, Ty. Never heard it called a smoke screw.

 

[m16ty]

Very nice job, Ty. Never heard it called a smoke screw.

I don't know but the more you turn it the more the smoke comes out of that big pipe sticking up on the passenger side.

 

[Kohburn]

why not a 24v to 12v transformer

can pick them up online for 10$

 

[Big Earl]

ISSPRO makes a nice mechanical pyro, and they'll put a 24v bulb in it too

 

[hklvette]

why not a 24v to 12v transformer

can pick them up online for 10$

transformers don't run on DC.