If the trades on your account have reached such a drawdown that there are practically no funds left on your account, your trades will be closed forced. In this case it is said that you have reached a stop-out.
This happens if the collateral falls to 15% of your funds. Say, if you bought 10,000 dollars for francs (pair USD/CHF) and you have 15 dollars left in your account (with the required margin of 100 dollars with a leverage of 1:100).
Be careful! Do not allow a large drawdown, otherwise a stop-out will occur on the account.