Light ampage draw

AndyBike

Esteemed Pedelecer
Nov 8, 2020
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Or whatever it is. To be honest this is a bit confusing as it offers 3 options - 1A 1.5A or 2A
Scroll down to the bottom.
I've found out Gen 4 bosch performance cx has a lighting voltage of 12v. But the bit about ampage has me confused and i can find no reference to it either on the bosch specs page or on the exposure light manual.
This seems to be a very important set up step. Be nice to know what exactly they're referring to or how i go about finding such info out.

Mechanical im fine with. Can take stuff to bits, reassemble no probs - but electrical with its voltages, amps and all that has me totally flummoxed. I know theres folk here that breathe this and are as competent in it as i am stripping down a engine.

So what in frigs name are they talking about.
 

guerney

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Sep 7, 2021
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Are you certain it's 12V? I read somewhere that the diagnostic software can set it to 12V or 6V.

Here's a converter. For example a 12V 18W light would draw 1.5A, and a 6V 18W light would draw 3A:

 

AndyBike

Esteemed Pedelecer
Nov 8, 2020
462
206
Are you certain it's 12V? I read somewhere that the diagnostic software can set it to 12V or 6V.

Here's a converter. For example a 12V 18W light would draw 1.5A, and a 6V 18W light would draw 3A:

Yes to the 12v. its on Bosch's website for gen3 and gen 4 motors as being 12v only, and also if you google what voltage light etc it tells you - (but i always check on the manufacturers site for confirmations.

Theres nothing about 'wattage' on the Exposure site only how many lumen it is - 1000 and the lamps are Cree XHP35
But a google gives me a possible answer on the Cree website of xhp35.2 as being 12v, main drive current of 1050mA and a max power wattage of 13w

Though I'd need to confirm this exactly(given my light only states xhp35 not hxp35.2, though its probably the same thing). Plus it says it is one cree, but theres 3 in the lamp, so whether that means i multiply 3x13w(dont think so, but again i'd need a confirmation)

All in all, very helpful. At least im a bit further forward :cool:
 

soundwave

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May 23, 2015
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the leds in the light wont be running at full power because if they was they would melt and every light manufacture lie about the lm output.

my 8000lm light has a 6 cell batt and at full power wont even last for 60mins.
DSC_0150_01_01.JPG
 

AndyBike

Esteemed Pedelecer
Nov 8, 2020
462
206
The ones who tell fibs are usually the ones selling 'super high power' lights on ebay for 30 quid. Exposure are not that type of company.

My main light is an exposure toro mk12. The Fuse is one i want to be in flash mode and having both gives me the best of both worlds. Super bright main light and the less powered fuse for flashing duties, so its not to blinding for other road users.
Or alternatively I can have the fuse on full too for extra bright were theres no traffic to worry about.

Toro on full beam. I get 2h on this.
When its on flashing i get 14h, so as a result its reduced in brightness. The Fuse means i keep the 2h of super bright with the toro, but the flashing fuse makes for a safer road ride
mbr269.grouptest.exposure.jpg
 

guerney

Esteemed Pedelecer
Sep 7, 2021
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Yes to the 12v. its on Bosch's website for gen3 and gen 4 motors as being 12v only, and also if you google what voltage light etc it tells you - (but i always check on the manufacturers site for confirmations.

Theres nothing about 'wattage' on the Exposure site only how many lumen it is - 1000 and the lamps are Cree XHP35
But a google gives me a possible answer on the Cree website of xhp35.2 as being 12v, main drive current of 1050mA and a max power wattage of 13w

Though I'd need to confirm this exactly(given my light only states xhp35 not hxp35.2, though its probably the same thing). Plus it says it is one cree, but theres 3 in the lamp, so whether that means i multiply 3x13w(dont think so, but again i'd need a confirmation)

All in all, very helpful. At least im a bit further forward :cool:
As you say, many manufacturers lie about lumens. Also some LEDs are more efficient than others.

Once that light circuit is enabled, you can test the voltage using a multimeter, before connecting the light. Or ask the guy with the diagnostic software re: voltage.

According to page 5 of the manual, it can draw up to 2A. I think perhaps you should ask your dealer what max amps your version of the Bosch motor can provide, on that light circuit. Or err on the side of caution, set it as low as possible.

Deffo read the destructions.

 
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AndyBike

Esteemed Pedelecer
Nov 8, 2020
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Deffo read the destructions.
I included them in my first post ;)

But it doesnt give all the info which is what you've been supplying :cool:
 

guerney

Esteemed Pedelecer
Sep 7, 2021
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Says here it's 1400LM :eek:


The " :eek: " is because mine flashing 1800LM at night is terrifying to behold, and would surely cause accidents if used. I actually get nauseaus, viewing the horror of that mode. I only use epileptic fit inducing flashing mode during the day.

The instructions are a little sparse, and I don't know much about Bosch ebikes. Don't you need to buy a specific cable with a connector, which fits into the port for lights inside your Bosch motor, after that port is enabled by a Bosch dealer? The switch shown on this image shows a red and black wire, which should be positive and negative respectively. Be certain that red is positive, check with the light manufacturer. LEDs die rapidly with incorrect polarity.




I'd disconnect the battery, before you start connecting the light cable to the port. I'd also wrap some insulation tape securely around each of the red and black wire ends of that cable, to prevent them ever touching. Never let those wires of opposite polarity touch, even when the battery is not connected - there could be some residual current from capacitors inside the controller, which could cause problems if short circuited. A Bosch motor controller won't be cheap to repair or replace.

After connecting the battery, very carefully (without allowing the red and black wires to touch each other!) test for voltage using a multimeter. Also test polarity - red should be positive. Then disconnect the battery, while you follow the cable connector instructions on page 4 of the manual.

You'll need to connect the cable leading to the light and switch, to the port on your Bosch motor, using the connectors supplied with the cable for light, as shown on page 4 of the manual. It'll probably look similar to this, but for your motor:




Make sure that red is positive, check with the cable supplier. If red is positive: connect red to red, and black to black.

Personally, I'd solder and marine heat shrink, rather than use those connectors on page 4 (now that I've learned to solder :cool: )
 
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