Island Radio Operated Car Club

Racing Topics => Nitro Racing => Topic started by: gotnitro on April 10, 2011, 11:17:12 PM

Title: lipo glo igniter
Post by: gotnitro on April 10, 2011, 11:17:12 PM
What can take a 7.4v lipo down to 1.5v. So it can work for a glo igniter adapter. ?
Title: Re: lipo glo igniter
Post by: gotnitro on April 10, 2011, 11:20:05 PM
Also I have 2 11.1v lipos, what will make them go down to 1.5v for the adapter.
Title: Re: lipo glo igniter
Post by: Shawn68z on April 11, 2011, 12:09:29 AM
Quote from: gotnitro on April 10, 2011, 11:17:12 PM
What can take a 7.4v lipo down to 1.5v. So it can work for a glo igniter adapter. ?

A 1.5 Volt voltage regulator can do that.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=728-1029-1-ND

Title: Re: lipo glo igniter
Post by: Shawn68z on April 11, 2011, 12:10:54 AM
Quote from: Shawn68z on April 11, 2011, 12:09:29 AM
Quote from: gotnitro on April 10, 2011, 11:17:12 PM
What can take a 7.4v lipo down to 1.5v. So it can work for a glo igniter adapter. ?

A 1.5 Volt voltage regulator can do that.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=728-1029-1-ND

Never mind.  Doesnt support that much current.   How much current does a glow plug use?

Title: Re: lipo glo igniter
Post by: Shawn68z on April 11, 2011, 12:14:36 AM

What about a potentionator? You can wire it as a riostat (sp) , that way you can control the output voltage. ?

Title: Re: lipo glo igniter
Post by: Tom on April 11, 2011, 10:59:39 PM
You're going to be dumping way too much power.

You've got to go PWM, no two ways about it.

The answer is, not easily, unless you can find a solution someone else has come up with.
Title: Re: lipo glo igniter
Post by: Shawn68z on April 11, 2011, 11:30:24 PM

Na.   Linear Voltage regulator such as this one would be a good way to do it.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=296-8158-5-ND


Upto 9V input, and allows the output to be controled from 1.2V to 8V.   Deliveres 3Amps of current with only a .4 voltage drop.   $9.   So gerry, you can build a 2S glow plug ignition for about $15 in electronic parts.

Shawn
Title: Re: lipo glo igniter
Post by: gotnitro on April 12, 2011, 12:54:17 AM
okay thank you.
Title: Re: lipo glo igniter
Post by: Tom on April 12, 2011, 10:18:55 AM
What does a glow plug draw?

I'm guessing an amp for now.

So, 11.1 - 1.2 = 9.9 volts you're dropping, at an amp, which means 1 amp * 9.9 volts ~= 10 watts of wasted energy for every 1.2 watts of power out.

You're going to need a big heat sink.

I don't recommend this approach.
Title: Re: lipo glo igniter
Post by: weekend camper on April 12, 2011, 01:51:18 PM
1. So that would be "why" glo sticks usually come with 1.2v batteries? To reduce the wasted heat released from a larger pack?  (and to fit in your hand)

2. Was there a big heatsink involved on those starters that had the glo stick tied into the main battery?


Title: Re: lipo glo igniter
Post by: gotnitro on April 12, 2011, 02:09:07 PM
Picked up to standard sub c at battery direct for 4dollars all good for both my igniters. Nimh battery
Title: Re: lipo glo igniter
Post by: Shawn68z on April 12, 2011, 07:59:26 PM
Quote from: Tom on April 12, 2011, 10:18:55 AM
What does a glow plug draw?

I'm guessing an amp for now.

So, 11.1 - 1.2 = 9.9 volts you're dropping, at an amp, which means 1 amp * 9.9 volts ~= 10 watts of wasted energy for every 1.2 watts of power out.

You're going to need a big heat sink.

I don't recommend this approach.

Its not a good approach, but if you mount it inside your starter box (assuming its metal), then I would use the 12V from the main battery, and use the chasis as the heat sink.  It could work,but I am sure their is a better solution.