Use independent brand mobile phone battery chargers with caution -CHOICE # 376

Be cautious of mobile phone battery chargers that are of independent brand manufacture.

Though accidents involving battery chargers may seem to be seldom reported, consumers should stay on guard of the safety of such devices.

The Consumer Council, in collaboration with the Electrical and Mechanical Services Department, have conducted a safety test on 10 models of battery chargers.

Six of the samples are of mobile phone brands, and the result showed that they all fully passed the international standard on safety.

Consumers can, therefore, put their heart at ease to continue using these battery chargers of mobile phone brands.

However, the 4 independently-branded chargers included in the test fared differently; all were found with deviations of one kind or more from the standard:

Insufficient insulation distances between live parts or basic insulated wires to user accessible plastic enclosure and/or components on the output circuit (all 4 samples).

• Internal wire in contact with parts of the secondary circuit had only basic insulation instead of double insulation (2 samples).
•  Internal live wire was not reliably secured before soldering (3 samples).
• The plastic enclosure of one sample was of inadequate resistance to heat and it softened under heat and pressure.
• One sample provided only one protective impedance instead of two.
• Missing marking, symbols or instruction (3 samples).

Significantly, one sample could not withstand a high electric voltage when it was applied across the input and output of its transformer. This model was voluntarily recalled last month.

Battery chargers of independent brands are generally of a lower price than mobile phone brand models - a factor of their popularity among consumers.

The deviations detected in the test were considered to be of a relatively minor nature, there is room for improvement for the battery chargers concerned.

Consumers looking for an alternative choice to replace their battery chargers that came with the mobile phones upon purchase, could well consider some of the better quality independent brand models.

Users are advised to read the instruction before charging; never place charger in wet environment such as the bath room nor expose it to high temperature or strong sunlight; use socket outlet with independent switch and switch off the charger when charging is completed.