SATK22
19
Auxiliary Microswitch
The HIU is equipped with a contact, driven by a relay
incorporated in the circuit board, the intervention logic of
which can be programmed in accordance with requirements by
setting technical parameter t05.
Each event linked to operation of the HIU is linked to a
numerical value, according to the following table:
Closing of the contact on the occurrence of multiple events
conditions is programmed by setting parameter t05 to a value
corresponding to the sum of the single events/conditions.
We give some practical examples below:
example 1 - Driving an external primary flow pump, normally
OFF.
The contact must be closed if any HIU function is active (DHW
production, heating, pre-heating)
Parameter t05 must be set to: 1 + 2 + 4 = 7
example 2 - Distinction of consumption for DHW production
from total consumption (in combination with heat meter
equipped with dedicated function)
The contact must be closed both if DHW tapping is in progress
and if activation of the comfort function is requested
(pre-heating or recirculation).
Parameter t05 must be set to 1 + 4 = 5.
Closing of the microswitch is shown on the user interface by
the symbols shown alongside.
N.B. if the DHW recirculation function is enabled with t02 = 1
(see page 16) the auxiliary microswitch intervention logic
described above is not operational. In this case, the contact is
used to control the recirculation pump.
Connection
For information on how to access the dedicated terminals,
consult the “Electronic Circuit Board” section on page 22.
N.B.: the auxiliary microswitch can be used to drive electric
loads directly, taking account of the following operating limits:
Max. voltage:
230 V ac
Max.current:
3 A
If the electric load to be controlled is not included within the
parameters indicated an external relay must be interposed.
Events - Conditions
Value
DHW tapping in progress
1
Heating cycle in progress
2
Comfort cycle (pre-heating/recirculation) in progress
4
HIU OFF
8
Error not active
16
Error active
32
