Fix lot size and rounding value.

Hi Guru's,

Can any body tell me the differrent between Fix lot size and rounding value.

If Fix lot size is 55 and rounding value is 60,

PIR is 100.

After MRP run system is giving me two plan order of 55.

Then wat is important of rounding value.

Please explain me with EX.

Thanx in advance!

Regards,

Nilesh Ithape.