4
Enabled = BI (binary input)
The heat exchanger is only enabled if it is not locked by the heat exchanger enabling
function (see section 1.5.1) and when its binary input is closed:
– UE 17 of the PLC for heat exchanger WT1
– UE 16 of the PLC for heat exchanger WT2
– BE5 at the ModBus I/O (1402-0328O (4) for heat exchanger WT3
2
[Übersicht > Service > Wärmetauscher 1…3]
This menu can only be activated after the application key number has been entered!
Parameter
WE
Adjustment range
Freigabe
(Enabling)
EIN
EIN (on), BE (binary input)
4.2.1 Unrestricted sequence
If the flow temperature does not reach the target temperature (set point), the lead heat
exchanger is activated. If the output entered in
ON switching point
is not reached to increase the
flow temperature to the set point, the lag heat exchanger is activated. It supplies the remaining
energy required to heat the flow temperature.
The lag heat exchanger first stops running when the total of the modulation of all the heat
exchangers is smaller than the
OFF switching point
parameter.
2
[Übersicht > Parameter > Allgemein > Folgebetrieb]
Parameter
WE
Adjustment range
Folge (sequence) =
uneingeschränkt (unrestricted)
Outdoor tempera-
ture dependent
Outdoor temperature dependent, unrestricted,
parallel
EIN-Schaltpunkt
(ON switching point)
90 %
0 to 100 %
AUS-Schaltpunkt
(OFF switching point)
40 %
0 to 100 %
4.2.2 Outdoor-temperature-dependent sequence
The heat exchangers are enabled depending on the outdoor temperature. Above the
Tempera-
ture for enabling the sequence
,
only
the lead heat exchanger is enabled. The
Temperature for
enabling the sequence
parameter must be adapted to meet the energy demand and possible
output of the lead heat exchanger. A higher energy demand must be able to be achieved by lon-
ger operating times of the lead heat exchanger without loss of comfort.
EB 5571-2 EN
23
Functions of the heat exchanger