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Re: Driving lamps, etc. -Reply -Reply

To: Christopher Palmer <ctp@gbn.org>, DANMAS <DANMAS@aol.com>,
Subject: Re: Driving lamps, etc. -Reply -Reply
From: Ray McCrary <spook01@mindspring.com>
Date: Fri, 09 Jan 1998 23:48:57 -0600
Hi guys,
A one wire alternator is available (no regulator woes), and the brackets
that are used on the B can be easily modded to work.  Puts out 65-85 amps
or more depending on the unit.
Ray

 At 07:05 PM 1/9/98 -0800, Christopher Palmer wrote:
>Hey all,
>
>Sorry if this is an incongruous solution but:
>
>I converted my car (1275) to a modern (although Lucas) alternator and
>haven't looked back since.
>
>(1=A2)
>
>ctp
>
>
>At 4:15 PM -0800 1/9/98, DANMAS wrote:
>>In a message dated 1/9/98 5:01:56 PM Eastern Standard Time,
>>Matt.Kulka@hboc.com writes:
>>
>>> Okay, I can visualize getting a cheap ammeter and connecting it between
>>>  a battery post and cable to find out how much various things load my
>>>  charging system.  But you can't very well measure the draw of your
>>>  coil's primary and secondary circuits (because the alternator never=
 runs
>>>  without that load.)  As a point of curiousity, does anyone know how=
 much
>>>  juice it takes just to create the sparks?
>>>
>>>  Also, what the heck is the formula for watts, voltage and amperes=
 again?
>>>   I haven't used it since high school.
>>
>>Matt,
>>
>>Let's start with the last part first:
>>
>>1) Watts =3D Volts X Amps
>>
>>2) Amps =3D Watts/Volts
>>
>>3) Volts =3D Amps X Resistance
>>
>>4) Amps =3D Volts/Resistance
>>
>>Substituting 3 into 1, we have
>>
>>5) Watts =3D Amps X Amps X Resistance
>>
>>I wouldn't suggest that you try to measure the current drain. I would
>>recommend that you sit down with a pencil, a calculator, and your=
 schematic,
>>and calculate the loads, using the formulas above. The wattage ratings
for the
>>lights are readily available, but you might have to do a little guess work
>>with other things, such as the heater fan. Based on my own experience, I=
 can
>>give you some rough approximations, though (very rough).
>>
>>Heater fan - 5 amps or less
>>WS Wiper motor - 1.5 amps
>>WS Washer motor - 1 amp
>>Horns - 5 amps
>>Electric gauges - 0.1 amp each
>>Fuel pump - 3 amps (racing pumps might draw up to 15)
>>ignition coil (primary only - the secondary doesn't draw from the
alternator)
>>- 4 amps or less
>>Radio - Depends on the volume, but a good average is to calculate the amps
>>based on the rated output wattage
>>
>>Just the other day, on the Triumph list, a question was raised as to the
>>correct ratings for fuses. I calculated the loads on my TR6 on a fuse by
fuse
>>basis, and I reprint it here. The results should be very similar for any=
 of
>>the LBCs of the same era.
>>***********************************************************************
>>"RED" fuse - This fuse feeds all the tail, parking, marker, and dash=
 lights,
>>and  pulls less than 6 amps.
>>
>>"PURPLE" fuse. - This fuse feeds the glovebox lamp, courtesy lamps, trunk
>>light, the horns, and the hi-beam flasher. With the exception of the
horns and
>>the flasher, the load is less than 3 amps on this fuse. For a stock
headlight,
>>flashing the hi-beams pulls about 9 amps, and the horns draw around 5
amps. If
>>you have quartz-halogen lights, the current will be more, but you really
>>should have them on a separate, un-fused, power source anyway (yes, I said
>>"un-fused" - that is not a typo!), and they should be relay operated. It=
 is
>>very unlikely that you will have the doors, trunk, and the glovebox open
while
>>blowing the horn and flashing the lights. Even if you should do this and
blow
>>the fuse, the headlights, both hi and low beams, will still work, as they
are
>>fed from another circuit. The flasher merely bypasses the headlight=
 switch.
>>
>>"GREEN" fuse - This one is a little harder to determine, as you will=
 seldom
>>have all loads on at the same time, but the maximum load, with everything
on,
>>is about 20 amps. This fuse supplies power to almost all of the loads
that are
>>switched on with the key, the most notable exception being the ignition
>>circuit, which is fed directly from the key with no fuse.
>>**********************************************************
>>As you can see, you will have to consider the likely load combinations=
 when
>>figuring the maximum draw, rather than just adding everything up. For
example,
>>no need to include both the high beams and the low beams, unless you have
>>rewired your car so they can both be on at the same time. Also, no real=
 need
>>to figure the horns, as they are only used momentarily, and the battery=
 can
>>supply any over draw they might create for that short length of time with=
 no
>>problem.
>>
>>If anyone is interested, I would be glad to post my entire response to the
>>Triumph list here as well. It had to do with replacing the 35 amp Lucas
fuses
>>with 35 amp fuses from the auto parts store (don't do it!).
>>
>>Equation 5) should be looked at with interest. All wires have resistance.
>>Current through any wire produces wattage, or heat.  From 5), you can see
that
>>if you double the current, the wattage, or heat, is quadrupled!=
 Interesting,
>>eh?
>>
>>Dan Masters,
>>Alcoa, TN
>>
>>'71 TR6---------3000mile/year driver, fully restored
>>'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion -=
 see:
>>                    http://www.sky.net/~boballen/mg/Masters/
>>'74 MGBGT---3000mile/year driver, original condition, slated for a V8=
 soon!
>>'68 MGBGT---organ donor for the '74
>
>
>
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