Non Super Fringe Benefit payroll

Hi Thankyou for your response. I'm sorry I didn't explain properly what I'm trying to do. I work for a non for profit organisation which has PBI status. A few staff members are salary sacrificing an amount each week to their credit card this amount at 31st march will equal below the threshold to pay FBT. I have set up the payroll items expense in company contribution and also a liability account. when processing the payroll I have been reducing the earnings which is subject to tax and the Salary sacrifice amount into company contribution account. I have done a test on the payment summary and the amounts show correctly into FBT and Gross amount. I am not sure whether I am suppose to reduce the earnings or is there some other way of processing the payroll.