[TR] Randall's Headlight Conversion

Anthony Rhodes spamiam at comcast.net
Sun Apr 12 12:19:42 MDT 2015

Randall is correct, the primary difference in an otherwise stock TR2-4a is that an alternator will probably put out more power at idle than a dynamo.  But this is not necessarily an advantage. Since power draw can vary a lot, the alternator load at idle will vary as well. This makes idle RPM more variable

With a dynamo, at idle it has minimal output and therefore minimal additional load at idle.  If an alternator does not add any significant load at idle then it is also not supplying much power at idle, and is not an advantage over a dynamo

The approximately 5.5 amps reduction in power usage with LED headlights may not sound like much, but it is 25% of the full output of the C40 dynamo.  So this is a significant reduction.  I would also use LED tail lights to get another few watts of reduction.  Then you will have ample power from a dynamo.  

Regarding H4 LED replacements, I am not enthusiastic about those that require active cooling with a fan.  Those little fans fail all the time.  If the fan fails, then the LEDs will fry.  There are other designs which use passive cooling with braided copper cable heatsinks.  In testing, those seem to be holding up to the demands of cooling inside sealed headlight buckets.  

Here are the LEDs.  Http://goo.gl/LMdLHU


On Apr 11, 2015, at 2:00 PM, triumphs-request at autox.team.net wrote:

> Message: 2
> Date: Fri, 10 Apr 2015 14:22:10 -0700
> From: "Randall" <TR3driver at ca.rr.com>
> To: <terryrs at comcast.net>,    <triumphs at autox.team.net>
> Subject: Re: [TR] Randall's Headlight Conversion
> Message-ID: <55.AD.19845.10F38255 at cdptpa-oedge02>
> Content-Type: text/plain;    charset="us-ascii"
>> One question I forgot to ask.  Since the conversion is from 
>> either incandescent or Halogen bulbs, to LED's, does this 
>> mean the alternator conversion is no longer necessary?  Would 
>> the generator be able to keep up when headlights are not such 
>> a draw on power in cold weather night driving?
> Should be OK, as long as you don't sit in traffic for very long or make a lot of short trips.  The LEDs will certainly reduce the
> need for an alternator.
> -- Randall  

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