I'd say they're either fake or faulty. Are you able to load test them individually as it might only be one that is causing a problem?
Unless your charger features a discharge function, it's not going to be of any help here.
You could pick up a couple of 12V automotive halogen bulbs from Poundland for load testing.
You could pick up a couple of 12V automotive halogen bulbs from Poundland for load testing.
D
Deleted member 4366
Guest
I've got a feeling that something is restricting the current somewhere. I wonder if it's the battery box bms.
Try this: twizzle the end of one of those probe wires around one of the springs in the box. It has to be the final positive or negative, then close the lid as far as you need to to make good contact with the cells. Put the other probe on the same wire as near to the light as you can get it. Turn up the light to full power. The voltage shown on the meter is the drop down the wire. It should be milivolts, but I got a feeling that it's going to be much higher.
Try this: twizzle the end of one of those probe wires around one of the springs in the box. It has to be the final positive or negative, then close the lid as far as you need to to make good contact with the cells. Put the other probe on the same wire as near to the light as you can get it. Turn up the light to full power. The voltage shown on the meter is the drop down the wire. It should be milivolts, but I got a feeling that it's going to be much higher.
The simple question; is your new light tremendously brighter than your old light?
If it's not those are the readings you are going to expect, sadly similar to the old light.
When you look at the housing, cables and batteries it is not going to be a high current monster.
Its the normal case of Chinese boasting.
It will be brighter as it uses the principle that two LEDs in series will provide a higher light output than a single LED when operated at the same current.
If it's not those are the readings you are going to expect, sadly similar to the old light.
When you look at the housing, cables and batteries it is not going to be a high current monster.
Its the normal case of Chinese boasting.
It will be brighter as it uses the principle that two LEDs in series will provide a higher light output than a single LED when operated at the same current.
D
Deleted member 4366
Guest
You've got the probes crossed over from pos to neg. They both need to be on the same wire, so 0v when the light is off, then you should see something when you switch it on.
D
Deleted member 4366
Guest
One probe needs to go on the negative spring. The other probe goes anywhere on the negative wire as near the light as possible.
We're trying to measure the voltage drop along the negative wire. At the moment you're measuring the voltage between the positive and the negative.
If the batteries are OK, which should be true because there's no reason that they shouldn't be, then we's expect to see about 8v on the ends of the cells when the light is on full power. At the light end, you're getting 6.2v, which means that you're losing 1.8v between the light and the cells. Therefore, if the peoblem is outside the cells, you should be able to measure 0.9v drop between the cells and the light on each wire. That would confirm that the problem is between the cells and the light, not the cells themselves.
The problem could be the wires, connectors, battery box or switch.
We're trying to measure the voltage drop along the negative wire. At the moment you're measuring the voltage between the positive and the negative.
If the batteries are OK, which should be true because there's no reason that they shouldn't be, then we's expect to see about 8v on the ends of the cells when the light is on full power. At the light end, you're getting 6.2v, which means that you're losing 1.8v between the light and the cells. Therefore, if the peoblem is outside the cells, you should be able to measure 0.9v drop between the cells and the light on each wire. That would confirm that the problem is between the cells and the light, not the cells themselves.
The problem could be the wires, connectors, battery box or switch.
D8's instructions were in post #324:
http://www.pedelecs.co.uk/forum/index.php?posts/333421
Edit: Cross posted with the previous post.
D
Deleted member 4366
Guest
You should see zero volts on the meter when the light's switched off, but as soon as you switch it on, the meter should show something.
its the batt case bms as down 1v when the light is on cant see it being any thing else?
another thing is the led on the back changes from green to red and thats what it does when the power is low on a normal pack but does it not long after i turn it on.
another thing is the led on the back changes from green to red and thats what it does when the power is low on a normal pack but does it not long after i turn it on.
Last edited:
While we are discussing cree lights, well I supose I mean Bulbs and seeing as how I have lost my battery box and possibly dodgy batteries..... How do these stack up?
http://www.hopetech.com/product/1-led-light/
Cree XTE I presume is different to the ones in the cheap chinese lights..
http://www.hopetech.com/product/1-led-light/
Cree XTE I presume is different to the ones in the cheap chinese lights..
D
Deleted member 4366
Guest
Related Articles
-
MTF Enterprises announces acquisition of EMU Electric Bikes- Started by: Pedelecs
-
Wisper 806T folding bike wins Which? ‘Best Buy’- Started by: Pedelecs
-
Sustrans calls for protected cycle lanes- Started by: Pedelecs
-
Amazon launch their first UK e-cargo micromobility hub- Started by: Pedelecs
