GP Recyko+ Pro U411
GP has a line of both chargers and batteries, this charger includes a set of NiMH batteries and as can be seen on the label GP means the charger is free. This is reflected in the naming of the pack: it is only named for the batteries.
The charger can charge two or four AA/AAA batteries at a time and is usb powered.
I got the charger in a partial clear plastic pack.
The pack contains the charger, a usb cable, 4 2000mAh pre-charged NiMH AA batteries and a instruction sheet. The batteries will be covered in their own review.
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The charger has a micro usb connector for power input.
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There are two led indicator lamps, flashing when charging and steady when not.
The charger is rated for 1A input, this is a bit high for a total charge current of 0.6A. Notice the hole in the bottom, this makes it easy to remove the batteries.
The charger has the typical two level slots used for AA/AAA batteres.
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Measurements
- Slot #1 & #2 is in series.
- Slot #3 & #4 is in series.
- Power consumption when idle is 1.3mA from usb
- When not powered it will not discharge batteries.
- Trickle charger on NiMH is about 50mA
- Will charge from 0 volt with nearly 1A.
- Charge will restart charging after power loss, or battery insertion.
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The charger will charge for nearly 8 hours and then switch to 50mA tricke charge, charge current will vary with battery voltage.
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The two other slots looks the same.
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When using high capacity batteries the fixed charge time is not enough to fill the batteries.
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This charger do not care about the condition of the batteries, they call get the same charge.
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These batteries have to much capacity to be filled.
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An AAA cell has less capacity, the charger handles that by lower charge current and using the same charge time.
These batteries are just about filled.
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Putting full batteries in the charger is a bad idea, they get another full charge.
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2 or 4 batteries do not matter for charge speed or algorithm.
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Power consumption is about 0.7A, not the rated 1A, but this will depend on battery voltage.
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M1: 37,4°C, M2: 37,6°C, M3: 37,4°C, M4: 37,1°C, HS1: 43,2°C
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M1: 46,4°C, M2: 49,6°C, M3: 49,7°C, M4: 46,2°C, HS1: 52,3°C
When batteries are full the temperature will raise and stay that way for some time while waiting for the timer termination.
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The charger is fairly fast to start. The there is only one charge circuit it will time share between the two sets (1+2 and 3+4).
Conclusion
This is a very simple charger with timer based control, it works fine for empty 2000mAh AA cells or empty 900mA AAA cells, but not for anything else.
I will call the charger usable.
Notes
Here is an explanation on how I did the above charge curves: How do I test a charger