Date: Sat, 10 Oct 2009 23:39:21 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Brake light circuit current with trailer,
WAS: Re: No High Beams
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=response
all that may be true.
but the fact remains, .for some odd reason, yet undiscovered,....
an 8 am fuse blows, and a 16 doesn't.
if "It pulls power from the battery directly to light the trailer's bulbs
without
> additional loading on the brake light circuit."
if that statement was true ............an 8 am fuse would do the job.
Something is not right somewhere, I suspect.
I like basic simple stuff I understand, or have built myself.
I would feel I was loosing control and understanding of how it works......
were I too add a solid state powered converter.
I find it more useful to talk about #'s of filaments.
in your trailer you have two filaments on each side, whether it's one bulb
with two filaments in it, a tail light size one, and a brake light/turn
signal one, or two single filament bulbs, one tail light size, and the other
brake light/turn signal size, or brightness. No abuguity when talking about
it that way.
And do people realize that on a car with a two filament system, brake light
voltage goes through the turn signal switch in the neautral position.......
but when it's put to a turn position............say to the right, the right
'brake light' turns into the right turn signal, leaving only one brake light
on the other side ?
sure seems goofy to me. a 3 filament system is safer, and doesn't require
electronic trickery, etc.
I'd be afraid to say I'd put a 16 amp in an 8 amp circuit - people would be
screaming that I was going to burn up my van. lol.
As long as they work, and you're happy ....................and as long as
there are no electrons going where they shouldn't in a big rush of
voltagge......
as in an uncontrolled way ............then things are fine.
----- Original Message -----
From: "Rocket J Squirrel" <camping.elliott@gmail.com>
To: "Scott Daniel - Turbovans" <scottdaniel@turbovans.com>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, October 10, 2009 10:56 PM
Subject: Re: Brake light circuit current with trailer, WAS: Re: No High
Beams
> It's always been working. I'm sorry I'm so wordy, the point I try to make
> often gets lost in the exposition.
>
> The brake lights on the Vanagon work fine. They draw 4 amps when the brake
> pedal is depressed.
>
> When the trailer was connected, the 8A brake light fuse (fuse 8, 1984)
> popped when I depressed the brake pedal. This happened in August 2008 when
> I was ready to leave to Bend, and it happened again a few weeks ago the
> first time I hooked up the trailer after the move up here. In both cases I
> removed the blown 8A fuse and installed a 16A fuse and all the light
> worked fine.
>
> My assumption was that the trailer lights -- tail lights, there are only
> two bulbs there -- plus the van's brake lights were too much for a 8A fuse
> to handle.
>
> But I'd forgotten that I had installed a powered 3 to 2 converter in the
> engine compartment when I wired up the trailer pigtail. It works: when I
> measure the current going through fuse 8 with no trailer connected, I
> measure 4 amps. With the trailer connected, there is still only 4 amps. It
> pulls power from the battery directly to light the trailer's bulbs without
> additional loading on the brake light circuit.
>
> The lamps all work as they should.
>
> The measurements do not show any reason why an 8A fuse would pop but a 16A
> fuse would hold when the trailer is connected, because as I noted, adding
> the trailer does not add additional loading to the brake light circuit. 4
> amps, either way.
>
> --
> Mike "Rocket J Squirrel" Elliott
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
> Bend, OR
> KG6RCR
>
>
>
> On 10/10/2009 10:32 PM Scott Daniel - Turbovans wrote:
>
>> hi,
>> maybe in the last line you mean the brake lights, and not the tail
>> lights, come on when the brake pedal is pressed.
>>
>> so it's working then ?
>>
>> ----- Original Message ----- From: "Rocket J Squirrel"
>> <camping.elliott@GMAIL.COM>
>> To: <vanagon@GERRY.VANAGON.COM>
>> Sent: Saturday, October 10, 2009 10:05 PM
>> Subject: Re: Brake light circuit current with trailer, WAS: Re: No High
>> Beams
>>
>>
>>> You're right -- it's unclear whether the problem is fixed, or what the
>>> problem was that caused the fuses to pop.
>>>
>>> There are two flavors of 3 to 2 tail light converters: powered and
>>> unpowered. Unpowered do the conversion and power the lamps from the same
>>> circuits that drive the van's tail lights. Powered converters do the
>>> conversion but have a +12 wire to draw trailer lamp lighting current
>>> from
>>> the battery so the vehicle's lamp circuits don't see the load of the
>>> extra
>>> bulbs.
>>>
>>> I can tell the converter is working fine because the current through the
>>> fuse is 4A when there is no trailer connected, and 4A when the trailer
>>> is
>>> connected. The tail lights on the trailer do come on when the brake
>>> pedal
>>> is depressed.*
>>>
>>>
>>>
>>> ==================
>>> * Or even mildly sad.
>>> --
>>> Mike "Rocket J Squirrel" Elliott
>>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>>> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
>>> Bend, OR
>>> KG6RCR
>>>
>>>
>>>
>>> On 10/10/2009 6:17 PM Scott Daniel - Turbovans wrote:
>>>
>>>> so your problem is still not fixed ?
>>>> to me, that's not really quite clear.
>>>>
>>>> and .........re :
>>>> "The converter is designed to make
>>>> sure that no additional loading is presented to the circuit. "
>>>>
>>>> really ?
>>>> I never use them, but my understanding is that they are for converting
>>>> from a '3 filament system ' ( vanagon - a separate filament for tail,
>>>> turn, and brake )
>>>> to a '2 filament system' ( where there is tail, and brake, but brake
>>>> on
>>>> one side turns into turn signal when the turn signal is engaged - a
>>>> very
>>>> dumb system I think, and still, oddly, used in brand new American cars
>>>> .........without even amber turn signal lenses even ) ...
>>>> but ....
>>>> just divies up from 3 to 2, or .........where you are going the other
>>>> way ..........from 2 to 3 if there is such a converter.
>>>>
>>>> I would start over.
>>>> it could be that you have a bad converting gizmo.
>>>>
>>>> here is what I Actually recommend, which I have done to my utility
>>>> trailer and it works dead frickin' perfect.
>>>> Get motorcycle amber turn signals.
>>>> They are often mounted on a rubber stalk too, so bumping them doesn't
>>>> brake them off.
>>>> I have mine under the rear of my utility trailer .
>>>> this way, I have a nice 3 filament system with amber turn signals on
>>>> my
>>>> vanagon,
>>>> and same on my trailer.
>>>> And the turn signal and 4 way flasher can handle the load of 3 or even
>>>> 6
>>>> turn signal bulbs all flashing at once.
>>>>
>>>> I think you have a bad converter unit perhaps, or are trying to use it
>>>> incorrectly or something along those lines.
>>>> I don't trust sealed electronic gizmo's like that very much anyway. If
>>>> they work fine ......
>>>> but if any doubt, get rid of that thing and wire it to truly match your
>>>> Vanagon's system.
>>>>
>>>> then there won't be any balonie about blowing fuses etc.
>>>> Find a motorcylce junk yard - used mc turn signal assemblies are cheap
>>>> I
>>>> would imagine.
>>>> Scott
>>>> www.turbovans.com
>>>>
>>>>
>>>> ----- Original Message ----- From: "Rocket J Squirrel"
>>>> <camping.elliott@GMAIL.COM>
>>>> To: <vanagon@GERRY.VANAGON.COM>
>>>> Sent: Saturday, October 10, 2009 5:45 PM
>>>> Subject: Brake light circuit current with trailer, WAS: Re: No High
>>>> Beams
>>>>
>>>>
>>>>> A continuation of a side thread.
>>>>>
>>>>> On 9/29/09 I opened my big fat yap to comment on a thread in which a
>>>>> list
>>>>> member said that he was blowing high beam fuses after going to higher
>>>>> wattage lamps (see "No High Beams").
>>>>>
>>>>> I helpfully added that on my van, fuse #8 (fusebox, 1984) popped
>>>>> moments
>>>>> after applying the brakes when my little trailer was hooked up.
>>>>> Changing
>>>>> the 8A fuse to a 16A fuse* fixed the problem.
>>>>>
>>>>> I thought that contributing this anecdote to the thread would help
>>>>> illustrate how adding more or bigger bulbs to a lighting circuit might
>>>>> exceed the current rating of the fuse.
>>>>>
>>>>> Ohm's Law says one 21W bulb will draw 1.75A at 12V, and around 1.95A
>>>>> at
>>>>> 13.4V (alternator booted). With four 21W bulbs that's nearly 8A, which
>>>>> would pretty quickly pop the fuse, although it should have taken a few
>>>>> seconds, and not the brief moment that I witnessed. My guess was that
>>>>> the
>>>>> bulbs' inrush current** was responsible for the fast blow.
>>>>>
>>>>> In the thread, a couple list members took me to task for not taking
>>>>> current measurements, I was speaking through my backside. So I
>>>>> measured
>>>>> the currents:***
>>>>>
>>>>> Results:
>>>>>
>>>>> With stock-type brake lights, no trailer: 3.9 amps @ 13.4V (1.95A/bulb
>>>>> which is in agreement with the calculated 2A/bulb @ 13.5V.)
>>>>>
>>>>> With trailer: Exactly the same. I had forgotten that I had wired in a
>>>>> "powered" 3-to-2 tail light converter****
>>>>>
>>>>> So. Why the heck did the 8A fuse pop the first time I pressed on the
>>>>> brake
>>>>> pedal once the trailer was connected. The converter is designed to
>>>>> make
>>>>> sure that no additional loading is presented to the circuit. And my
>>>>> measurements confirm it. I think it's fair to say that if there was a
>>>>> momentary short or glitch in the trailer pigtail or wiring, the
>>>>> converter
>>>>> would have had to deal with it, not the dash fuse.
>>>>>
>>>>> I should point out that this scenario played out exactly the same way
>>>>> back
>>>>> in August 2008 when I first hooked up the trailer for my Escape From
>>>>> SoCal.
>>>>>
>>>>> Science is baffled.
>>>>>
>>>>>
>>>>> ==========
>>>>> * These GBC "ceramic torpedo" fuses only come in three flavors: 8A,
>>>>> 16A, 25A
>>>>>
>>>>> ** Inrush current, I felt, was the reason why the fuse was popping so
>>>>> quickly since light bulbs will draw 5 to 10 times as much current
>>>>> when
>>>>> power is first applied than when they are hot.
>>>>>
>>>>> *** My reader will recall that I can't be trusted with an ammeter:
>>>>> none of
>>>>> my ammeters have intact fuses in them. I've blown them all. To make
>>>>> these
>>>>> measurements I made a 0.01 ohm (+/-) "resistor" using 19'' of 40-mil
>>>>> diameter solid-core copper wire soldered across a blown fuse. By
>>>>> measuring
>>>>> the voltage drop across this current-sampling resistance and applying
>>>>> I =
>>>>> E/R I had my ammeter. Easy as cake.
>>>>>
>>>>> **** The trailer has two bulbs, one on right, one on left, Vanagon
>>>>> uses
>>>>> four bulbs: right turn, left turn, and two brake lights wired
>>>>> together,
>>>>> three circuits total. A converter is needed to drive the two-circuit
>>>>> trailer from the three circuit van. A powered converter connects to
>>>>> the
>>>>> battery to avoid additional loading on the original lighting circuits.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Mike "Rocket J Squirrel" Elliott
>>>>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>>>>> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
>>>>> Bend, OR
>>>>> KG6RCR
>>>>
>>>>
>>
|