If you are interested in applying in both shareholders and retail categories, you are eligible for a maximum limit of ₹200,000 in each category (A total of ₹4L).
If you are only applying in the shareholder's category, you can apply for as much as you want.
As per DRHP "An SBI Shareholders bidding in the SBI Shareholders Reservation Portion above ₹200,000 cannot Bid in the Net Offer (retail category) as such Bids will be treated as multiple Bids."