Paytype set up for hours just to get accrual leave

We have a scenario where an employee has 40 hours ordinary time . This is used as one of the basis to calculate his pay and annual leave

But on top of the normal annual leave, he may be given additional accrual leave based on that 40hours with different table method calculation

How do I set up a Paytype  without any effect on his pay/monetary amount but just to include it as a basis of calculation to another form of leave accrual I will create with a different table method.