NPS deduction

Section 80CCD
Employee can contribute to Government notified Pension Schemes (like National Pension Scheme – NPS). The contributions can be upto 10% of the salary (or) Gross Income and Rs 50,000 additional tax benefit u/s 80CCD (1b) was proposed in Budget 2015.
To claim this deduction, the employee has to contribute to Govt recognized Pension schemes like NPS. The 10% of salary limit is applicable for salaried individuals and Gross income is applicable for non-salaried. The definition of Salary is only ‘Dearness Allowance.’ If your employer also contributes to Pension Scheme, the whole contribution amount (10% of salary) can be claimed as tax deduction under Section 80CCD (2).
Kindly note that the Total Deduction under section 80C, 80CCC and 80CCD (1) together cannot exceed Rs 1,50,000 for the financial year 2016-17. The additional tax deduction of Rs 50,000 u/s 80CCD (1b) is over and above this Rs 1.5 Lakh limt

i want to know being a salaried person my total deduction was 1 lakh...can i claim 50k in 80c n 50k in 80 ccd 1b?

If your contribution to nps is <= 10% of your salary, you can claim the same

U/s 80C you can claim Rs 50000 if it is within the band of 10% of your salary income. Remaining 50000 you can claim u/s 80CCD (1B)

For eg My salary is 10 lakh..NPS 10% is 1 lakh..50k i claim in 80c n 50 k in 80 ccd 1b and this is legal...right?

Yes. Its correct and as per law.