The overheating she refers to occurred on a small sub board that provides charging current to the battery string. It happens that we made a minor change in location of the board when we started full production that moved it out of an area of greater air flow and the heat sink needed to be increased to preserve the cooling level of a power transistor. It did not overheat in our bench tests, and many units in the field never experienced overheating. In hifigeekgirl's case it did overheat. The result was a recurring alarm and descriptive error code raised by the on board diagnostics which was presented on the front display. The PurePower+ automatically protected itself from overheating by shutting down the regeneration and charger. That doesn't seem too stupid to me.
The engineering change required to remedy the problem was very simple and effective. Increasing the heat sink size by 50% reduced the component temperature to well within acceptable operating range and even continuous operation at 100% load did not increase the charging board operating temperature. |
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