OW detection when negative cell voltage

The open-wire detection on the S pins uses a resistor between the SxP and SxN connections to look for a change in cell voltage.  So without a voltage to move some small current across that resistor it wouldn't be detectable near 0V even if the S-ADC could measure below 0V.  With battery cells typically a range check is sufficient for avoiding this near 0V case.

Are they measuring fuel cells for this application or is it still battery cells?  If batteries, why the negative voltage requirement?  If it's a busbar in the stack you can use the adjacent 2 cell S-ADC connections to check the busbar wire connections, all while leaving the SxP and SxN of the busbar channel open.

The open-wire detection on the S pins uses a resistor between the SxP and SxN connections to look for a change in cell voltage.  So without a voltage to move some small current across that resistor it wouldn't be detectable near 0V even if the S-ADC could measure below 0V.  With battery cells typically a range check is sufficient for avoiding this near 0V case.

Are they measuring fuel cells for this application or is it still battery cells?  If batteries, why the negative voltage requirement?  If it's a busbar in the stack you can use the adjacent 2 cell S-ADC connections to check the busbar wire connections, all while leaving the SxP and SxN of the busbar channel open.

To add to this, here is the OW circuit marked in case C15 disconnects (RED cross), when the OW switch(circled in BLUE) is closed, it introduces a 18kOhm+2kOhm resistor across the cell which will translate as change in cell voltage.

Thanks for your reply.
However, if the cell voltage is -1.2V to +3.5V, this usage is not possible because it exceeds the absolute maximum rating, right?

If the SxP and SxN for the cell x which is negative are not connected, then it is okay if the C pin differential voltage is negative, and will not exceed any absolute maximum.  The differential voltage between C pins may be as low as -6V.