Xing Mini Charger

Model Airplane News, Apr 2001 by Aberle, Bob

DYMOND MODELSPORT USA

All charged up!

This small, peak-detect (auto cutoff) fast charger is capable of handling from 4- to 7-cell Ni-Cd packs at selectable current levels of 1, 2 and 4 amps. It comes in a red-anodized, extruded-aluminum case that's only 4 inches long. Input power (12 volts DC) is applied via a pair of 16-inch wires that end in alligator clips. This input is reverse-polarity protected and contwins a 10A fuse for added protection (accessible from the outside of the case). The output consists of a small terminal block with screw contacts. A 3 1/2inch cable that ends in a Tamiya connector is also provided, but any popular connector could easily be substituted.

When power is first applied to the Xing (say "zing"), a yellow LED indicates that power is on. Then you connect a 4- to 7-cell battery pack, and the middle LED glows green (in addition to the yellow LED). At this point, you select your charge current of 1, 2, or 4 amps. The final step is to press the start button, at which time the third LED glows red. The battery pack is now on fast charge (all three LEDs continue to glow).

When the peak-charge current is reached, the Xing automatically shuts down (the red LED goes out), and the unit reverts to a pulsed trickle-level charge (the yellow and green LEDs continue to glow). I measured the average trickle current at about 200mA when using the 1A charge rate, about 250mA for the 2A rate and close to 300mA when charging at the 4A level. At those rates, I wouldn't leave the packs on the charger for a long time; just use it to keep your pack topped off at the field while you get ready for your next flight.

You do need to use the slide switch to select the right charge current for your particular battery capacity. Failure to choose the correct current could lead to over- or undercharging. The instructions supplied are not very informative on this subject, but a small chart on the outside of the shipping box suggests that 600 to 1,000mAh Ni-Cd batteries should be charged at 1 amp, 1,30mAh cells at 2 amps and 1,700mAh cells at 4 amps. Battery packs with capacities between these values will need a little more or less time to charge but are nothing to worry about. I also recommend charging packs as small as 275mAh on the 1A rate, since this would equate to only a 3C rate. Keep in mind that it usually takes about 20 minutes to fully charge a completely discharged battery at the 3C rate. I noticed that even at the 1 A charge rate, the Xing did get quite hot to the touch; be sure to allow air to flow around it while it's in use to help dissipate some of the heat it generates.

The instructions also make it clear that RC system receiver packs (usually 4 or 5 cells) should be charged only at the 1A level because many of these packs employ relatively lightweight wiring, and placing more than 1 amp on this fine wire might actually melt it.

All in all, this little charger worked reliably every time. Although somewhat limited by its ability to charge only 4 to 7 cells, at the list price of $39.95, it's a bargain. Small enough to easily tuck away in a field kit, this is one very neat little product! -Bob Aberle

Dymond Modelsport USA Ltd., 683 N. Main St., Oshkosh, WI 54901; (920) 303-1100; fax (920) 303-2021; www.rc-dymond.com.