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33. Regulation (Model TH-3xxSx1)
All the graphics below refer to automatic speed control.
The fan is a 3 speed on/off model, the outputs are defined as follows:
- digital output
DO1
for speed 1
- digital output
DO2
for speed 2
- digital output
DO3
for speed 3
Parameters
I29
,
I30
,
I31
,
I32
and
I33
are not used in this type of regulation.
• HEATING mode (
M01
=0)
The “
HEAT
” icon is on to indicate that heating mode is active.
The regulation logic is as follows:
Temp.
BHS
(
I07
)
PBH
(
I22
)
100
0
Output valve
speed 1
% opening
valve
Fan
speed 3
(
I25
)
0%
100%
speed 2
(
I26
)
(
I27
)
AO1
DO1
DO2
DO3
If the operating temperature drops below
I07,
the valve
starts opening (output
AO1
). Icon turns on.
The valve can be regulated with PI action if the integral
time
I24
is non-zero or with only proportional action if
I24
=0.
The fan starts when the valve reaches the aperture de-
fined in
I25
and after startup delay
I36
.
If the temperature continues falling, the speed switches
from speed 1 to speed 2 when the valve reaches the ap-
erture given in
I26
. The speed switches from speed 2 to
speed 3 when the valve reaches the aperture given in
I27
.
Each speed is subject to a hysteresis of 20% of its activa-
tion point.
For example, for speed 3:
if
I27
=100%, speed 3 is activated when the valve reaches
fully open and is deactivated when the valve closes by
20% of
I27
, which is 80% of fully open in this case.
Icon turns off when the valve closes again, in which
case the fan stops if
I28
=0 or 2. The fan maintains speed
1 if
I28
=1 or 3.
The fan maintains speed selected manually if
I28
=4 or 6.
N.B.: if the minimum thermostat function is active, the thermostat itself must be closed when the valve is in regulation,
otherwise the fan will not start.
Wiring diagram
N L
DI
1
GN
D
DI
2
AI1 GN
D
AI2
DO
1
DO
2
GN
D
T1
T2
S1
S2
M1
I
II
III
DO
3
CO
M
N
L
230V
ac
V1
AO1 GN
D
G
G0
24V
ac
Y G0
A +
B
-
MODBUS RTU
(TH-xMxxx)
