There are two ways to keep the electric strike / door open for a specific period of time:
1. By software
Using the command RLY=0 and RLY=1 to permanent engage the electric strike. And use the HB=60 to call the web server in 60 seconds interval. If the call is inside 9:00am to 5:00pm, send RLY=1 to engage the electric strike. Otherwise, follows the normal authentication procedures.
2. By hardware
Using a external timer unit with relay out with connect in parallel to the web based reader, so either circuit can engage the electric strike.