User`s guide

Establishing Communications
Remote Access
Release E UMC800 Control Builder User’s Guide 35
1/01
Using remote access
• From the Main Window Communications menu,
select “ Setup”. The “Communications Setup” dialog
box will appear.
• Click on the “Modem” radio button in the Comm Link
Port Settings on the “Communications Setup” dialog
box.
In communication setup, you cannot select Modbus
RTU as a protocol plus a modem because Modbus
RTU uses a 3-character dead-time to delimit packets
of data and can cause a problem over the phone.
Note also that the Modem/Comm Link selection is not
persistent. This setting defaults to "Serial" every time
the application is started.
• The Telephony setting becomes active
Select No Timeout (no timeout is performed and the
application will stay connected until you manually
hang up.
Select Connection Timeout (Enter, in minutes, how
long the application will leave the line open before
hanging up automatically.)
For example, if you have selected a 10 min. timeout,
the application will check back in 10 minutes. If a
communications operation is in progress, the
application will try again in another 10 min. It will
keep checking at 10-minute intervals forever, or until
it finds that there is no communication operation in
progress; then it will hang up.
Application tip: If you want to do initiate a download
and leave while the download is in progress, set the
timeout to 1 min. That way, the application will keep
checking at 1-minute intervals to see if the download
is done. When it is, the application will disconnect
the call.
• Click “OK”.