datsun-roadsters
[Top] [All Lists]

Re: Speaking of Lighting

To: "Thomas Walter" <walter@omni.sps.mot.com>,
Subject: Re: Speaking of Lighting
From: "Calvin Grandy" <cmgfam@sover.net>
Date: Tue, 16 Nov 1999 13:38:55 -0500
Thomas
That diagram is worthless!

I admit that drawings are a problem with text as drawing tools, but drawings 
should make things clearer.
I tried a bit of "text art, but could not justify the method so I do not offer 
to do better.

In text:
Wiring a RELAY involves a low current circuit (the control side) that controls 
a high current circuit.(the load side)
The manually switched circuit (control side) gets a current source from the 
battery, thru a small capacity fuse from the dash fuse box(<10 amps?) or such, 
then to the dash switch. The headlight switch is useful if you wish to control 
the head lights.  The wires then connect to  the control, or coil, connection 
of the relay and then return to the battery + through chassis ground.  The only 
thing "wired" in this circuit is the hand switch to the relay.  The wires can 
be of small gauge.  If all is well, you just hear a click in the relay when the 
switch is turned on.  Measurement of the LOAD contacts would show a closed 
circuit there too.

The relay is really an electrically activated switch!  

The load side needs a wiring circuit that includes a heavier fused source (25 
amps?) from the battery to the switched portion of the relay.  When the relay 
is activated, (closed) the current flows from the battery through the relay to 
the lights(load) then through chassis ground back to the battery.  These wires 
need to be rated for the lamp load.  Two 100 watt lamps + about 17 amps.

There are two distinct circuits.  Low current for the manually switched  
circuit, and high current for the lamps themselves.

Is this "better? than the drawing?  I can't say, but like Thomas, I tried.

Regards

Calvin Grandy

----------
> From: Thomas Walter <walter@omni.sps.mot.com>
> To: datsun-roadsters@autox.team.net
> Subject: Re: Speaking of Lighting
> Date: Tuesday, November 16, 1999 12:15 PM
> 
> John,
> 
> If you are using the "fog light switch" (seperate switch on 67.5
> roadster, and a "rotate the headlight knob 90 degrees on original
> 68-70 roadsters) then, yes you need a relay!
> 
> I always go for a good quality relay. Hella, Siemens, Bosch
> all make good decent relays. Avoid the "Made in Taiwan" stuff.
> Decent auto parts store carry good relay (avoid major retailers
> as they seem to stock the cheap taiwan stuff).
> 
> As to hooking up the relay:
> 
>                                              RELAY
> 
>                                              -----
> o------o~~~o---------------------------------0    0----- lights
> bat    fuse                                                
>                    fog light lead -----------()()()----- ground
> 
> 
> 
> Seperate Fuse.
> When the headlights on on, and you turn on the relay switch
> you should head a "click" sound. At least you'll know you
> wired that part of the relay correctly.
> 
> My brother is a CFO for a hospital, bright CPA type... still
> can not figure out how to wire up a relay.
> 
> Cheers,
> 
> Tom
> 
> 
> >
> >With all of the talk of headlights I have a question about wiring for
> >driving lights.
> >
> >I had installed a set of the JC Whitless driving lights with a 100 watt
> >bulb.  I hooked them up to the original equip power source and after using
> >them for 2 mins checked the fuse box.  It was already very hot so I haven't
> >used them since.
> >
> >The alternative would seem to be a relay switched on and off by the light
> >switch.  The power for the lights themselves would then have to be an
> >alternative source. That all makes lots of sence but how do I wire all of
> >this.  I am not a Tom Walter so I need help.  Where would I get a relay for
> >this and is there a specific type/rating that I would need to use?  Do I
> >run the source directly from the battery or from the front end of the fuse
> >box?  Do I use a fuseable link or is the relay a fuse?  See,  I dont really
> >know anything !!
> >
> >I have never seen an FAQ on this so if I missed it forgive me.
> >
> >John Schmitt    Telecommuter Office # - 847-458-7829
> >   Internal phonemail only  -  847-240-4725      pager pin#  800-759-8888
> >pin 8710561
> >
> >
> >

<Prev in Thread] Current Thread [Next in Thread>