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Offline B0M0A0K

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The BMW battery charger - Is it specialised?
« on: September 26, 2020, 10:26:00 AM »
I have seen a number of folks using the dedicated BMW battery charger and was wondering if it did something specific to BMW. I have used an Optimate 4 for many years and have always found it to be outstanding at keeping my batteries in good health. Is there something about the BMW that trumps what the Optimate 4 can do?
« Last Edit: September 26, 2020, 10:26:56 AM by B0M0A0K »
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Offline RadioFlyer

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Re: The BMW battery charger - Is it specialised?
« Reply #1 on: September 26, 2020, 02:47:24 PM »
Of course BMW wants to promote its own charger.

The substantive concern is that one does not connect a "smart" charger having a desulphation mode. If the smart charger decides that the battery is sulphated it hits it with high voltage pulses. These pulses could possibly damage the bike's electronics. Your Optimate 4 has two modes. If you use it in the "CAN-bus" mode (a misnomer) you can safely use it either through the accessory port or direct to the battery.

Both the BMW charger and the Optimate 4 can do the handshake with the ZFE to keep the accessory port open for charging.