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Breva 11 headlight... again...

pswiatki said:
General note about vehicle lights:
my uncle, who is a professor of physics, worked with lasers a lot and has superb knowledge in optical instruments and theory of optics gave me the following advice:
I asked if it would be a problem, to put an orange LED light in the indicator. He said it could work, but since the enclosure is made so that its surface is a matrix of small lenses and there is a curved mirror-like surface behind the bulb - it is important to have the source of light at the precise location for the optics to work as designed. If it is misaligned, the light could be diffused and the indicator could emit it in undesirable directions. The incandescent bulb is seated at such precise location in the indicator with the assumption the filament within the bulb itself will be at the (more or less) proper location as well. Then the optical arrangement works as expected.

So, I presume, it gets much worse (as far as optical properties are concerned) with larger lamps, such as the headlight. If you take a headlight which was designed for incandescent bulbs where filaments are expected to be at their designated locations for the mirror behind and (possibly?) the glass in front (or lens in high beam reflector) to do their jobs properly. H7, H4 or other LED-"bulbs" have rows of LED structures which cannot be located at the same place where the filament is in the incandescent equivalent (that is: in the centre of the bulb).
So, putting in such LED "bulbs" may produce suboptimal results. It is therefore much better to go for a completely new, LED-based headlight assembly. Hope this helps.
Click to expand...
I don't doubt you are correct, and I appreciate the information a great deal :clap:
 
Well, it turns out I am getting a full 13.7 V at both headlight sockets when the bike is running, just as at the battery. so I don't think a relay is going to do very much. if I am wrong, I would be happy to be informed...
 
ah... it does occur to me that I'm neglecting the question of amperage. I'll put the meter on again today.
 
okay... I have slowly and laboriously educated myself a bit on the bike's electrical system. testing the voltage properly, I have less than 10.6V at the headlight socket, under load. which no doubt explains why it's thoroughly useless.

so I have ordered a relay kit.

will continue to update
 
I am debating if a semi-conductor module in place of a (bunch of) relays could be another solution. I guess it could only be added as additional equipment rather than replacement of the existing relays. ECU most probably senses the current in the relay coil circuit, so those original relays must stay as they are. But for any additional circuits it could make some sense. Also, semi-conductor based switching in light circuits could allow for PWM control of brightness. We will see, I shall experiment.
 
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tobinh said:
okay... I have slowly and laboriously educated myself a bit on the bike's electrical system. testing the voltage properly, I have less than 10.6V at the headlight socket, under load.
Click to expand...

So why did it change from 13.7v as per your previous post?

The better voltage to read would be between the battery positive and the headlight socket to find out what your voltage drop is.

Have you researched "Startus Interruptus" as pswiatki referred to?

 
tobinh said:
okay... I have slowly and laboriously educated myself a bit on the bike's electrical system. testing the voltage properly, I have less than 10.6V at the headlight socket, under load. which no doubt explains why it's thoroughly useless.

so I have ordered a relay kit.

will continue to update
Click to expand...
Be very careful with this now. If you have a faulty connection (say, at the headlamp connector) causing this voltage drop you may experience something like this. I imagine it could happen when high-beam is active and both high power bulbs draw current (more or less 10A). A major flaw in this circuit is over-current protection - only the global 30A fuse at the battery protects everything. This is really bad.
 
kiwi dave said:
So why did it change from 13.7v as per your previous post?

The better voltage to read would be between the battery positive and the headlight socket to find out what your voltage drop is.

Have you researched "Startus Interruptus" as pswiatki referred to?
Click to expand...
I have a startus inerruptus installed on the bike, did it years ago as a precautionary measure. I installed it and it works fine, but my understanding of what it's doing is pretty surface level.

the voltage changed because I wasn't testing it properly - I was testing the socket without the bulb, so the circuit was not under load. I just don't know much about electrical systems, so this is all a learning process for me, and testing the H9 socket with the bulb installed is kinda tricky.

when I tested it with the bulb on, by making up a little tester / jumper / harness, it dropped to the 10.6. I did some more research that suggested it should be more than 12.5ish with the bulb lit.
 
pswiatki said:
I am debating if a semi-conductor module in place of a (bunch of) relays could be another solution. I guess it could only be added as additional equipment rather than replacement of the existing relays. ECU most probably senses the current in the relay coil circuit, so those original relays must stay as they are. But for any additional circuits is could make some sense. Also, semi-conductor based switching in light circuits could allow for PWM control of brightness. We will see, I shall experiment.
Click to expand...
haha I can't say I understand all of this, but it sounds lovely. please keep us updated!
 
pswiatki said:
Be very careful with this now. If you have a faulty connection (say, at the headlamp connector) causing this voltage drop you may experience something like this. I imagine it could happen when high-beam is active and both high power bulbs draw current (more or less 10A). A major flaw in this circuit is over-current protection - only the global 30A fuse at the battery protects everything. This is really bad.
Click to expand...
oh, I've also ordered a fuse box to connect everything to.

my actual aim was to reduce all the leads going to my battery, basically to keep things organized, but the added fuse protection will be good too!

it's this one :)

ah... I don't think I'm allowed to link stuff here actually...
 
tobinh said:
ah... I don't think I'm allowed to link stuff here actually...
Click to expand...
I just ask that hyperlinks to competing products not be inserted here. Hyperlinks that allow easy clicks away from this site help with competition's SEO (Search Engine Optimization) and take away from it here. You can insert urls here without the http://www typically without it auto-linking. Also, products I sell help support this website.
 
GT-Rx® said:
I just ask that hyperlinks to competing products not be inserted here. Hyperlinks that allow easy clicks away from this site help with competitions SEO (Search Engine Optimization) and take away from it here. Also, products I sell help support this website.
Click to expand...
right, I understand. I deleted it because this little fusebox I found could be construed as a competitor to the motogadget M-Unit... although vastly simpler.
 
tobinh said:
right, I understand. I deleted it because this little fusebox I found could be construed as a competitor to the motogadget M-Unit... although vastly simpler.
Click to expand...
Post it, I'll revise the link as needed.
 
Interesting that mUnit is, indeed. I understand it controls the stoplight by sensing the deceleration using an on-board accelerometer?
Also, I wonder if one could replace those relays that are controlled by the DSB module (i.e. cluster) by the mUnit.
I believe it would immediately trigger a DTC in the DSB (with a possible pop-up on the main display).
Unless of course, the mUnit puts enough load on the control line to fool the DSB into thinking it is a normal relay.

I have one general question: routing power (on any vehicle) where both cables, PWR and GND are run from [say] battery, along the main harness, to the load, isn't, probably, the proper way of doing it, or it can be tolerated?
Whenever I see GND network on the electrical diagram I see a short connection to the ground symbol nearby (e.g. the headlight assembly and front direction indicators). Does it imply the frame and engine block are used as the return path to ground?
On the other hand - any accessory I added used a red/black dual-wire cable to connect to the power source. While it is easier to hook up, I wonder if it is the "correct" way - especially for higher current circuits.
 
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tobinh said:
oh, I've also ordered a fuse box to connect everything to.

...the added fuse protection will be good too!
Click to expand...
Yes, it is very much true. The added protection is good to have (as I found out). Do I remember correctly that high-beam means both bulbs (H7 55W and H9 65W) are lit?
 
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pswiatki said:
Yes, it is very much true. The added protection is good to have (as I found out). Do I remember correctly that high-beam means both bulbs (H7 55W and H9 65W) are lit?
Click to expand...
yes that's right.

also the parking bulb is on with the low beam.

I didn't know this... in fact mine was burned out and I didn't even know. I replaced it with a little LED that actually does, I think, make me noticeably more visible on the road to other traffic.
 
OK... Perfect. We are talking 55+65W = 120W. That is almost 9A @13.7V and 10A @12V. So, better to have good cables and connectors. I will replace cables (because I have to - they are burnt), add a dedicated fuse and possibly a relay, too.
 
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pswiatki said:
OK... Perfect. We are talking 55+65W = 120W. That is almost 9A @13.7V and 10A @12V. So, better to have good cables and connectors. I will replace cables (because I have to - they are burnt), add a dedicated fuse and possibly a relay, too.
Click to expand...

Use two relays, one for each bulb.
 
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