Salus Limited. ST880ZB ユーザーズマニュアル
ST880ZB / Optima USA
Rev. 3.9
Form No. : F-ENG-1023A
Page 36 of 38
2. This should not be affected by system change. For example. If the mode is heat pump heating, changing to cooling
mode will shut off the compressor and it will be locked out until after delay time.
Residual cooling fan delay
1. After cooling is turned off, fan will continue to run for a specific period of time.
2. While the fan is operating in the extended period, if the user changes the system mode from COOL to others, the
2. While the fan is operating in the extended period, if the user changes the system mode from COOL to others, the
fan will turn off and the delay timer will be reset.
Auto season changeover
1. If system is set to Auto, the thermostat will determine heating or cooling system automatically.
2. Auto season changeover will be temporarily disabled in Temporary hold and Vacation hold. For Temporary hold, the
2. Auto season changeover will be temporarily disabled in Temporary hold and Vacation hold. For Temporary hold, the
system when the hold is activated will be maintained. For Vacation hold, it is always the heat mode or off.
3. Auto season changeover will be temporary disabled during the recovery process,
4. For Program mode, if the room temperature is higher than or equal to the cool set temp, and also higher than or
4. For Program mode, if the room temperature is higher than or equal to the cool set temp, and also higher than or
equal to the heat set temp + deadband, switch the system to cooling control. If the room temperature is lower than
or equal to the heat set temp, and also lower than or equal to the cool set temp - deadband, switch the system to
heating control.
or equal to the heat set temp, and also lower than or equal to the cool set temp - deadband, switch the system to
heating control.
5. For Program mode, it is assumed that the cool setpoint is always higher than or equal to the heat setpoint.
6. For Permanent hold, if the room temperature is higher than or equal to set temp + deadband, switch the system to
6. For Permanent hold, if the room temperature is higher than or equal to set temp + deadband, switch the system to
cooling control. If the room temperature is lower than or equal to set temp - deadband, switch the system to heating
control.
control.
7. Otherwise, set the system to the same as the last controlled system.
Protection
Heat cut off at high temperature
When room temperature is too high, all heating outputs will be turned off regardless of the control pattern and delay
timers.
timers.
Cool cut off at low temperature
When room temperature is too low, all cooling outputs will be turned off regardless of the control pattern and delay
timers.
timers.
Relay state feedback
Latching type relays are used which is susceptible to vibration. State of the relays is continuously monitored. It will be
corrected if it does not match the correct state.
corrected if it does not match the correct state.
Temperature sensing error
If there is error in temperature measurement, “- -“ will be displayed on the room temperature and the thermostat will turn
off all the relays.
off all the relays.
Temperature sampling
1. Temperature sampling rate should be 4 times per minute or faster.
2. Temperature sampling should be put on hold if there is possible instability in electrical or temperature. For example,
2. Temperature sampling should be put on hold if there is possible instability in electrical or temperature. For example,
during LCD backlight or RF is on (could affect the AD circuit?) or the user is setting the thermostat (could affect the
surrounding temperature?). Final implementation will be decided base on the design and test result.
surrounding temperature?). Final implementation will be decided base on the design and test result.
3. Moving average or other methods is required to reduce influence from temperature fluctuation or possible
temperature reading error.