The default timeout for VISA Read and Write is 2000 milliseconds, but if you wish to change this, the timeout can only be set for an entire VISA session. This means that the timeout will be the same for both VISA Read and VISA Write.
To set the timeout for a VISA session, create a Property Node for the VISA session and select the Timeout attribute from the dropdown menu. The timeout attribute can be defined by wiring the desired value for timeout in milliseconds. This can also be done by using VISA Set Timeout in LabVIEW (located in the Functions palette under Instrument I/O»VISA»VISA Advanced) or the viSetAttribute("VI_ATTR_TMO_VALUEK") function in LabWindows™/CVI™.
The following code snippet shows an example where the timeout is set to 2 seconds: