Limit Price Protection or LPP is the mechanism to define the price range for the Limit Orders if these order types are placed out of that range they will be rejected.

Suppose the index option is trading at ₹100, since the premium is more than 50, the LPP range will be ±40% from the LTP i.e. upper limit of ₹140 and a lower limit of ₹60. So if you place a buy limit order above ₹140, your order will be rejected, similarly, if you place a sell limit order below ₹60, your order will be rejected.

The same applies to the SL-Limit order, since the LPP check is applied post-trigger on SL-L, the system will allow you to place order out of LPP range, but will not execute post-trigger. But you are open to place buy limit order below the lower limit of LPP and sell limit order above the upper limit.

Similarly, if the index option is trading at ₹30, since the premium is less than 50, the LPP range will be ±₹20 from the LTP i.e. upper limit of ₹50 and lower limit of ₹10. And if the limit order and SL-limit (post trigger) are placed out of this range, it will be rejected.