Rotex Controller Series, Продуктовая документация

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EbV Product documentation THETA NORM/UNIT
10-4
10.3.2 Switch-off behavior
The number of stages is reduced as soon as the boiler temperature of the leading
boiler or the common flow sensor exceeds the current set boiler temperature plus
half of the switching differential during the calculated switch-off delay.
The switch-off delay is reduced if the actual temperature is far above the switching
differential. The reduction is proportional to the ratio
dFT = Difference nominal flow temperature and actual flow
temperature
FT
nom
= nominal flow value
SD
cascade
= 1/2 cascade switching differential
10.3.3 Operation with boiler control (old)
• The switching order of the condensing boilers connected to a standard unit always
corresponds to the set address of the heat generator bus interface (RS485
interface) and can not be changed by parameterization. The management for the
control of the boiler control only transfers the number of stages to switch on to the
cascade management. Therefore, the boiler temperature of the boiler control with
the smallest address in the system is determined and activated for control.
• The registry of the burner running time only influences the boiler control with the
smallest address.
• For condensing boilers, the switch-over power may also be transferred (see
Page 10-2).
10.3.4 Operation with conventional heat generators (2-point)
Function: Only the heat generator that was switched on last operates according to the setpoint
(residual heat coverage). All other heat generators are switched on.
Only after the corrected stage has no more demands on the heat generator and the
boiler temperature rises above the setpoint plus the set cascade switching
differential, the boiler stage can be reduced by one.
Each heat generator displays the current demand value as setpoint.
If a heat generator is not available in the system (error, external blockage or OUT-
lock), it is skipped in the stage control and the next available heat generator is
controlled.
The minimum boiler temperature of all the burner stages enabled by the cascade
management is checked. In such cases the highest minimum temperature of all the
heat generators is set as the minimum requirement for the system.
The maximum boiler temperature is only monitored inside the heat generators. There
is no limit to the setpoint!
dFT - SD
cascade
/ 2
FT
nom
+ SD
cascade
/ 2