Subject: RE: Relays
Author: Gary Cheek
Date: Feb 16, 2004, 9:28 AM
Post ID: 1716056618
Good article Ross,
There are a few differences when working on bikes from cars. With cars
the wire usually travels a longer distance . With bikes due to short
wire run you can easily feed most headlamps with 16 gauge wire . Of
course there is no harm done with heavier wire . Also the author is
using 4 terminal relays that have the coil on terminals 85 and 86 ,the
common or movable armature terminal is #30 and the normally open
terminal is Bosch designated as #87 . These numbers apply to the 4
terminal Mini and Micro Bosch type relays.
Just as a note many motorcycle applications use the 5 terminal micro
relay . With these relays the coil terminals are often listed as #1 and
#2 ,the common terminal is #3 , #4 is normally closed and #5 is the
normally open .
The added normally closed contact gives options later on that include
turning the headlamp off when the driving lights are switched on ,
flashing the high beam when the horn is blowing etc. The late Moto
Guzzis use the extra contact to turn the head light off while the
starter is cranking . I will show some of the options later on for those
interested.
The author makes the advantages very apparent in the article you
posted . It is a pity that Guzzi still runs the headlamp through the
ignition switch and the headlamp switch contacts . The "headlight" relay
is really only used to turn the light off while cranking ,the other
switches and 20 gauge wiring still handle the full current load.
For the sake of conversion :
4 Terminal 5 Terminal
#85 #1 (coil)
#86 #2 (coil)
#30 #3 (common -C))
#87 #5 (Normally Open -NO)
DNA #4 (Normally Closed -NC)
The relay can save those old snuff box switches from meltdown and
provide better lighting to boot . They also head off the fuse block
Chernobyl inside the headlight from a high resistance fused connector
trying to sullpy current to the headlight ! There are worthwhile
upgrades for the fuse block down the road too ...........
Thanks Ross for an excellent link !
Ross wrote:
| Some may find this interesting. It is directed towards auto but the principles are the same: http://www.danielsternlighting.com/tech/relays/relays.html --- K. Ross Raymond Arizona, USA 1971 Moto Guzzi Ambassador LAPD 1969 Triumph T100S 1975 Norton Interstate MkIII 1998 Ariel (my daughter, named after the sq4 not the mermaid) |
Not a business just a hobby