Delay in reading data from lab balance

[PSGPES]

Hi I am trying to write a very basic VI to record data from lab balance. LabVIEW receives data from the balance but only after a time delay which get longer the greater amount of time the programme runs for. I have attached the VI and the manual for the balance. Can anyone suggest why this is happening?

I have checked I have the same baud rate. 

[ben64]

Page 35 of the manual, you need to send the s or w command to the balance to receive data.

Ben64

[PSGPES]

Do you know how I would implement this as part of my VI?

[RavensFan]

Add a VISA Write right before the VISA Read.