This ProBuilder code snippet demonstrates how to halt trading activities in an automated trading system after incurring a significant loss, specifically a 5% drop in equity. The code uses conditional statements to monitor and update the trading status based on the equity level after each trade.

ONCE BigLoss = 0.95 //5% or more has to be considered a big loss
ONCE TradeOn = 1 //Trading enabled by default at launchtime
ONCE Capital = 10000 //Set your initial capital

IF NOT OnMarket AND OnMarket[1] THEN //When a trade is closed ...
    IF (Capital + StrategyProfit) <= (Capital * BigLoss) THEN //... check if it's a big loss and ...
        TradeOn = 0 //... eventually stop trading
    ENDIF
    Capital = Capital + StrategyProfit //Update your Equity
ENDIF

IF Your_Conditions AND TradeOn AND Not OnMarket THEN
    BUY/SELLSHORT .......
ENDIF

Explanation of the code:

• Initialization: Three variables are initialized at the start:
  • BigLoss: Set to 0.95, representing a 5% loss threshold.
  • TradeOn: A boolean flag initialized to 1 (true), allowing trading to commence.
  • Capital: Represents the initial capital, set here as 10000.
• Trade Closure Check: The first IF condition checks if a trade has just closed (i.e., not currently on the market but was on the market in the previous period).
  • If the total equity after the trade (Capital + StrategyProfit) is less than or equal to 95% of the previous capital (indicating a 5% or more loss), the TradeOn flag is set to 0 (false), halting further trading.
  • The capital is then updated by adding the strategy profit or loss from the last trade.
• Conditional Trading: The second IF condition allows new trades (either buy or sell short) only if the custom conditions (Your_Conditions) are met, trading is enabled (TradeOn is true), and the system is not currently in a trade.

This approach ensures that the trading system pauses operations after a significant loss, potentially safeguarding against further undesirable drawdowns until conditions are deemed favorable again or manual intervention resets the trading flag.