Reading my WF-139

[Corey R.]

Hi -

I have an UltraFire charger and need help reading the LED status lights.

When i place in my batteries both sides are red and briefly blink green, then back to red.

What does this mean?

I have used the light lightly over the last few weeks and the lights still read the same.

Can someone help me decode this and other status lights (charging / fully charged / trickle) the charger may throw?

 

[CaseyS]

On mine, purchased a couple months ago from 4sevens:

No cells loaded: solid green
Charging: as you described, red flashing to green
Fully charged: solid green

If you have a recent model, it shouldn't trickle charge.

 

[Hondo]

I have the TR-001, which is similar, but the lights stay on solid red when charging. Termination is good at 4.18 on both channels, with some current flow after, but still not exceeding 4.20 volts if left on for 2-3 hours after green light.

I believe that the green flash when charging is the result of your charger pausing to check battery voltage, and is normal.

It does not sound like you have a volt meter, and if you are using Li-Ion batteries, you should get one. You don't need anything fancy to measure battery voltage, but it is usually worth it in the long run to get a model with current measurement capability, particularly one that can go up to 10 Amps.

 

[WHT_GE8]

On my WF-139 the light stays red when its charging. I have no idea when its done because ive only used it once. I was on there for about 6 hours and it was still red, so I just used them. The 18650's werent even dead but were low. I dont have any kind of meter to measure stuff. :shrug:

 

[Black Rose]

I dont have any kind of meter to measure stuff. :shrug:

If you are using Li-Ion cells, you need to have a DMM to check the voltage of the cells.
That's the best way to know their state of charge.

 

[WHT_GE8]

So the WF-139 charger has absolutely no way of indicating when the batteries are fully charged?

 

[Black Rose]

The LEDs turn green when it is finished.

 

[TooManyGizmos]

ALL newcomers to batteries and chargers should read the stickies and threads at the TOP of this battery forum.

Learn what to do , how to do it , and do it safely .

Some posters I've seen in this Forum don't seem to have a clue , but they're playing with FIRE anyway !

 

[Henk_Lu]

ALL newcomers to batteries and chargers should read the stickies and threads at the TOP of this battery forum.

Learn what to do , how to do it , and do it safely .

Some posters I've seen in this Forum don't seem to have a clue , but they're playing with FIRE anyway !

+1000!

I still haven't any of my stuff, but I read everything I find because fortunately I know that there are risks.

The problem is, depending on where you buy your stuff, you are not informed about possible dangers. The ignorant people here will at least be informed, but how many are outside and think charging batteries is like buying new ones, only cheaper?

I've been using rechargeable li-ions in cell phones and laptops for over 10 years now and I until I got on CPF I didn't have the slightest clue what's inside that stuff and that it could potentially be dangerous. Worse, as I was used to NiCd and memory effect from the past, I thought that it even if li-ions have no memory effect it was good treatment to suck them dry, as neither I knew about over discharging.

Well, all this sounds dramatic, but 95% of the people also think fueling a car is safe as long as they don't use a lighter to check if their tank is full and they never heard that you can provoque a gas explosion just by getting back in your car while the fuel flows, charge yourself with static energy and produce a spark touching the fuel pistol afterwards? These phenomenons are rare, so nearly nobody knows, until it happens...