The HVD/HVDR function of Morningstar controllers is designed to halt charging when battery voltage rises to dangerous levels due to another charging source in the system. It also is used to disconnect voltage sensitive loads from the system. There are two types of HVD; charging disconnect and load disconnect. When the battery voltage rises above the HVD charging threshold due to another unregulated charging source in the system, charging is halted by the Morningstar controller. Charging resumes when the battery voltage drops to the safe HVDR threshold.Loads are disconnected when the battery voltage exceeds the HVD load threshold. This is in order to protect voltage sensitive loads from a high voltage input. Loads are reconnected when the battery drops to the safe HVDR threshold.

Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology


Tech Support Policy

TriStar MPPT Processor A Firmware Update

v32b Firmware and above addresses EEprom access bugfix causing watchdog trip and subsequent lowside FET turn on.  This issue is generally limited to Controllers installed in applications utilizing all, or most, of the following items in the design.  -High I/O of Communications, -Read/Write of vb_ref register (0x0033), -Read/Write of ib_ref register (0x0058), -Write of battery current limit (0xE01D), -Coil command restart of controller, -48V Systems, -Oversized Arrays.  The following link provides instructions on updating firmware:


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