19ST620 INSTRUCTION MANUAL
RADIO CONTROLLED CLOCK
The ST620 time and day of the week settings are updated automatically
every day (at 12:00 AM or 2:00 AM) by the use of a very accurate internal
Radio Controlled Clock.
The RCC status indicator will be displayed for 10 minutes during clock
updates. The indicator will flash during the time update process, after which
the indicator will be displayed for 5 minutes before turning off.
The time and date will also be automatically updated when the ST620 is
powered up, or after the Reset Button is pressed.
If for any reason the ST620 fails to automatically update the time setting, then the data stored in the
internal memory will be used. The clock settings can also be changed manually if required – manual
settings will be overwritten at the next successful automatic update.
CONTROL MENU
By selecting the Control menu, the user can
change the control method used by the
thermostat - either ON/OFF or Pulse Width
Modulation(PWM). On entering the menu,
scroll to select the preferred option (ON/OFF
or PWM control), and confirm the choice
using the OK button. Use the Arrow key to
return to the Menu Option display. PWM
mode should only be selected by the Engineer carrying out the installation, or other qualified person.