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EV.8.4 Accumulator Voltage‌

EV.8.4.1 The AMS must measure the cell voltage of every cell

When single cells are directly connected in parallel, only one voltage measurement is needed

EV.8.4.2 Cell Voltage levels must remain inside the allowed minimum and maximum cell voltage levels stated in the cell data sheet. Measurement accuracy must be considered.

EV.8.4.3 All voltage sense wires to the AMS must meet one of:

a. Have Overcurrent Protection EV.8.4.4 below

b. Meet requirements for no Overcurrent Protection listed in EV.8.4.5 below

EV.8.4.4 When used, Overcurrent Protection for the AMS voltage sense wires must meet the following.

a. The Overcurrent Protection must occur in the conductor, wire or PCB trace which is directly connected to the cell tab.

b. The voltage rating of the Overcurrent Protection must be equal to or greater than the smaller of:

 The sum of the cell voltages sensed by the AMS board

 The sum of the cell voltages sensed between galvanic isolation boundaries on the cell board/AMS

EV.8.4.5 Overcurrent Protection is not required on a voltage sense wire if all three of the following conditions are met:

 AMS is a distributed AMS system (one cell measurement per board)

 Sense wire length is < 25 mm

 AMS board has Overcurrent Protection

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