Eco-King HWB-299, Installation And Service Manual

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E93.1801EN171 HWB installation manual 96
16.2.5 C
ASCADE
– S
TART
/
STOP SEQUENCE
The managing water heater sends the calculated Cascade_Setpoint to the dependent water heaters. The power
of the water heaters is PID controlled based on the Calculated_Setpoint and T_Supply. Depending on the temper-
ature difference between T_System and Cascade_Setpoint (DHW) the dependent water heaters will start or stop
using different algorithms.
Quick Starting and Stopping Water heaters
When there is a big difference between the T_System and the Cascade_Setpoint the call for a start or stop of the
next or last depending is done quicker.
16.2.6 C
ASCADE
– P
OWER BALANCE MODE
Several different power control modes can be selected to operate the cascade system.
• Power mode 0: Power control disabled, each water heater modulates based on the system setpoint.
• Power mode 1: Power control algorithm to have a minimum amount of water heaters/water heaters active.
• Power mode 2: Power control algorithm to have a maximum amount of water heaters/water heaters active.
• Power mode 3: Power control algorithm to have a balanced amount of water heaters/water heaters active.
Cascade – Water heater rotation
The water heater rotation function can change the start/stop sequence for the cascade water heaters.
The parameter Water heater_Rotation_Interval sets the number of days after which the sequence is updated.
When Water heater_Rotation_Interval is set to 0 water heater rotation is disabled.
When the parameter Burner_Rotation_Interval is updated the water heater rotation days left will be initialized to
the new
Burner_Rotation_Interval setting.
When for example Burner_Rotation_Interval = 5 the start sequence is as following (x is the last water heater):
Days Start/Stop sequence
Day 0-5 1-2-3-4-5..x
Day 5-10 2-3-4-5..x-1
Day 10-15 3-4-5..x-1-2
Day 15-20 4-5..x-1-2-3
Day 20-25 5..x-1-2-3-4
With parameter First_Depending_To_Start the current depending that is first to start in the sequence is selected.
When the water heaters are rotated the parameter First_Depending_To_Start is automatically updated to the next
depending. When water heater rotation is disabled the parameter First_Depending_To_Start is reset to 0.
When the First_Depending_To_Start is manually changed the control will clear all demand of the cascade control.
After this is will start cascade demand generation with the new selection for First_Depending_To_Start.
16.3.1 N
EXT DEPENDING TO START SELECTION
When the cascade Burner_Rotation_Interval has passed the control will perform the cascade rotation. At this
moment the next available control based on the current First_Depending_To_Start is selected.
A depending control is available when the control is present on the communication bus and the control is not
blocked by an error.
When the control is not available the control is skipped as the next First_Depending_To_Start.
Relevant variables
Specific Parameters Level (Default) Value Range
Burner_Rotation_Interval 2: Installer 5 0…30
(0: Disabled)
First_Depending_To_Start 2: Installer 1 1…8/16