Honeywell SDC Service Manual page 213

SDC / DHC
Buffer sensor 2 (BS2)
EN2H-0221GE51 R0812
Depending on the activated buffer control mode, activated tank
discharge protection must act on the buffer instead of the heat
generator. The required conditions can be seen in the following
table.
Tank discharge
protection/heat
generator available
Tank discharge
protection/heat
generator not available
Buffer sensor 2 (BS2)
As an option, the buffer tank can be equipped with the second
buffer sensor (BS2) via the variable inputs, for stratified loading.
The buffer is loaded through the active heat generator as soon as
the higher temperature (of the two sensors) undershoots the
setpoint value. Loading though the heat generator is terminated
when the lower temperature (of the two sensors) has reached the
setpoint plus the set buffer switching differential (stratified loading)
Buffer loading pump extended running time
When buffer loading of a buffer loading system is complete, an
extended running time for the buffer loading pump can be
configured via a parameter setting.
Buffer control mode
1 2 3
Buffer Heat Heat
gene- gene-
rator rator
Buffer Heat Buffer Heat
gene-
rator
Hydraulic Components
4 5 6
Heat Heat Buffer
gene- gene-
rator rator
Heat Buffer
gene- gene-
rator rator
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