Position margin under isolated margin mode
In isolated margin mode, it depicts the margin placed into a position is isolated from the trader's account balance. In the event of liquidation, the trader will only lose all of his position margin (excluding funding fees). Hence, the position margin under isolated margin mode is:
Position margin (isolated margin mode) = initial margin + fee to close.
Replenishment of position margin under isolated margin mode
When a trader pays funding fee for a position, the funding fee will be deducted from the available balance at every funding timing (00:00 UTC, 08:00 UTC and 16:00 UTC) and this will result in the position's liquidation price to move closer to the mark price and increase the risk of liquidation.
To avoid this from happening, traders can make deposits, perform asset exchange increases or release order margin from cancelling active orders to replenish their position margin or increase the available balance. However, do note that, under different contracts and different scenarios, the process of replenishment to position margin will be different too.
Position margin under cross margin mode
When a trader is using cross margin mode, it uses all of a trader’s available balance within the corresponding trading pair coin type to prevent liquidation, hence the display of the position margin will be different from isolated margin as it will now occupy the available balance to cover the unrealized loss.
Position margin (cross margin mode) = contracts balances +∑PNL in cross margin.