Why does a twin charger only charge one battery at a time?

Why does a twin charger only charge one battery at a time? trimble charger dual battery slot The Dual-Slot Battery Charger with Power Supply can be used with the Spectra GNSS comes with two slots and can accommodate two batteries at a trimble dual slot battery charger manual I have two grey batteries for my S3 total station I have the two slot grey charger When I charge one of the batteries

trimble dual slot battery charger manual Dual Slot Charger for RTS and MT1000GPS Batteries Share Related products

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