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[BufferFlex] function block
Configuration parameter
Example:
[Buffer target] = 70 °C
[Flow temp raise] = 5 °C
=> The accumulator tank demands 75 °C from the
boiler. The boiler target temperature is therefore 75°C.
Explanation of [Enable temperature]
This parameter defines the minimum temperature of
the boiler for charging the buffer. Buffer charging can
only occur when the boiler has exceeded this tempera-
ture.
Explanation of [Switching at]
This parameter is used to set the duration for switching
between boilers in cascade systems. This serves to
ensure that the operating period is approximately
identical for all boilers.
In order to switch between the individual boilers,
all boilers must have the same [Boiler order]
setting.
Explanation of [Switch-on threshold]
This parameter can only be set if several heat
producers charge the buffer. This parameter makes it
possible to change the threshold for requesting
another heat producer (e.g. second boiler for charging
the buffer).
Example:
2 boilers with 90 kW output each charge the buffer.
The parameter [Switch-on threshold] is set to 100%.
=> If more than 90 kW (e.g.: 95 kW) is requested, the
second boiler will be activated in order to produce the
missing heat volume (5 kW).
However, if parameter [Switch-on threshold] is
set to 110%, it is possible to request a total of 99
kW (=110% of 90 kW) from the buffer without
actuating the second boiler. This is only activated if
more than 99 kW is requested.
Explanation of [Switch-off threshold]
This parameter can only be set if several heat
producers charge the buffer. This parameter makes it
possible to change the threshold for swtiching off the
additional heat producer (e.g. second boiler for
charging the buffer).
Example:
2 boilers with 90 kW output each are currently
charging the buffer. The parameter [Switch-off
threshold] is set to 80%.
=> If the demand on the boiler falls below 72 kW
(=80% of 90 kW), the last activated boiler will be
switched off again.
Explanation of [Desired charging time]
This parameter defines the time required by the boilers
to charge the buffer to the required target temperature
[Buffer target].
In cascade systems (several boilers charge one
buffer), adjusting this parameter may be helpful
for faster buffer charging. Shortening this time causes
other boilers to fire up sooner to help charge the buffer.
Lengthening the time would extend the running time of
an individual boiler.
Explanation of [Buffer off]
This sets the shutdown temperature for the buffer
charge when the consumer is in operation while
requesting heat from the buffer.
If the temperature sensor in the buffer has exceeded
the shutdown temperature, charging of the buffer ends
and the buffer is charged.
If several consumer levels are configured, a
different shutdown temperature can be set for
each level.
