Plan - Current sensors

Sensing and reporting battery current to an Elithion Lithiumate™ BMS

In order to operate properly, the BMS controller needs to know the battery current.

The source of information for the battery current depends on how the BMS controller is powered:

When the controller is powered through its "VL" pin (Load Voltage):	When the controller is powered through its "VS" pin (Source Voltage) (for example, when plugged into the AC outlet):	When the controller is powered through both "VL" and "VS" pins:
It must know the value of the Load Current (for example to and from a motor controller) You must program the controller to look for it from a specific source of information	It must know the value of the Source Current (for example from a charger) You must program the controller to look for it from a specific source of information	The controller adds both values as the total battery current Therefore, you must make sure that the same current is not counted twice: Don't use the same source of information for both Load and Source current Don't route both Load and Source current through a single current sensor

The source of information on the battery current can be digital or analog, and can be one of the following:

Digital: some other device on the CAN bus that knows the current and reports it. For example:	Analog: a current sensor connected to one of the 3 analog inputs on the BMS controller:
A motor controller that includes a battery current sensor and reports it on the CAN bus A charger, such as the Brusa, that includes a battery current sensor and reports it on the CAN bus A Remote High Voltage Front End with a built-in current sensor	The "External Current Sensor" 4-pin connector on the controller The "SRC" pin on the "Control" connector on the controller The internal harness between the controller and its HVFE in a BMS controller with High Voltage Front End with a built-in current sensor

In particular:

For the Load Current:

For the Source Current:

One and only one source of information must be used and selected That selection is independent of the selection for the Source current Typically, a cable mounted current sensor is used, connected to the "External Current Sensor" connector on the controller With a Remote High Voltage Front End with a built-in current sensor, all you need to do is connect both it and the controller to the CAN bus, and the rest is done for you

One and only one source of information must be used and selected That selection is independent of the selection for the Load current Typically, an in-line current sensor is used, connected to the "SRC" pin on the "Control" connector on the controller With a Brusa charger, all you need to do is connect both it and the controller to the CAN bus, and the rest is done for you