Tech Controllers ST-979, Руководство пользователя

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TECH
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 Modulation
In this mode Cascade controls CH boilers operation in order to reach the pre-set temperature.
First, one boiler is activated. Once its maximum is reached, the user-defined waiting time elapses
(Waiting time parameter). If the pre-set temperature is not reached within this time, another
boiler is enabled. If the pre-set temperature is still not reached despite both boilers operating at
full speed, it is followed by another waiting time period and another boiler is enabled. The
procedure is repeated until the pre-set temperature is reached or until all boilers are active.
Once the pre-set temperature is reached, the boilers are selectively disabled every 20
minutes. The deactivation procedure is repeated until one of these conditions is met:
1. CH temperature drops below the pre-set temperature by hysteresis value;
2. only one boiler remains active.
NOTE
Regardless of the mode selected, boilers operation time is registered in order to
ensure even wear of the boilers. This information is used by the cascade controller
to decide which boiler should be enabled or disabled.
VI.b) Time settings
This function is used to set current time. This setting is essential for the weekly control to work
correctly.
VI.b.1) Clock settings
This parameter is used to set current time.
VI.b.2) Date settings
This parameter is used to set current date.