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32. Control with 3 speed ON/OFF motor (Model TH-2xxSx1)
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 proportional action only if
I24
=0.
The fan starts when the valve reaches the aperture given
by parameter
I25
, and after the fan start delay
I36
has
expired.
If the temperature continues to fall, the speed switches
from speed 1 to speed 2 when the valve reaches the ap-
erture given in parameter
I26
. The speed switches from
speed 2 to speed 3 when the valve reaches the aperture
given in parameter
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 if the valve closes again, in which case
the fan is stopped if
I28
=0 or 2. The fan stays at speed 1 if
I28
=1 or 3.
If
I28
=4 or 6, the fan stays on at speed selected manually.
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
AI3 GN
D
T1
T2
S1
S2
T3
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)
