Carel ir33 Universale series User Manual page 28

ENG
output, that is, for ON/OFF operation, the deactivation point of the output
or, for PWM operation, the point where the output has the minimum value
(ON time =0). If the output refers to St1 ("dependence"=1), "diff erential/
logic" is relative to the percentage value of P1; if the output refers to St2
("dependence"= 2), "diff erential/logic" is relative to the percentage value
of P2.
If the value of "diff erential/logic" is positive, the deactivation point is
greater than the activation point and "reverse" logic is created.
If the value of "diff erential/logic" is negative, the deactivation point is less
than the activation point and "direct" logic is created.
Together with the previous "activation" parameter, this identifi es the
proportional control band.
Example 3.
Example 3 completes example 1, adding the deactivation points.
For the fi rst output "reverse" operation is required, and the diff erential P1;
for the second, "direct" logic and the diff erential equal to half of P2.
The parameters are :
Output 1 : "diff erential/logic"=c37=+100 (A')
Output 2: "diff erential/logic"=c41=-50 (B')
A'=10; B'=21.5
OUT1
A A'
c37=+100
c36=-100
P1=6 P1=6
St1=10
Key
St1/2 Set point 1/2
c36/c40 Activation of output 1/2
c37/c41 Diff erential/logic for output 1/2
OUT1/2 Output 1/2
P1 Set point diff erential 1
P2 Set point diff erential 2
B1 Probe 1
As an example, reversing the values of "diff erential/logic", the new
deactivation points are as follows
Output 1 : "diff erential/logic"=c37=-50(A')
Output 2: "diff erential/logic"=c41=+100 (B')
A''=1; B''=30.5
OUT1
A'' A
c37=-50
c36=-100
P1=6 P1=6
St1=10
5.5.5 Activation restriction (par. d34,d38,d42,d46)
In normal operating conditions, the activation sequence should be as
follows: 1,2,3,4. However, due to minimum on/off times or times between
successive activations, the sequence may not be observed. By setting this
restriction, the correct sequence is observed even when timers have been
set. The output with the activation restriction set to 'x' (1,2,3) will only be
activated after the activation of output 'x' . The output with the activation
restriction set to 0 will be activated irrespective of the other outputs.
ir33 universale +030220801 - rel. 1.0 - 16.04.2008
OUT2
ON
B' B
OFF
B1
c41=-50
c40=+75
P2=6 P2=6
St2=20
OUT2
ON
B
OFF
c41=+100
B1
c40=+75
P2=6 P2=6
St2=20
5.5.6 Deactivation restriction (par. d35,d39,d43,d47)
In normal operating conditions, the deactivation sequence should be as
follows: 4,3,2,1. However, due to minimum on/off times or times between
successive activations, the sequence may not be observed. By setting
this restriction, the correct sequence is observed even when timers have
been set. The output with the deactivation restriction set to 'x' (1,2,3) will
only be deactivated after the deactivation of output 'x' . The output with
the deactivation restriction set to 0 will be deactivated irrespective of the
other outputs.
5.5.7 Minimum modulating output value
(parameters d36,d40,d44,d48)
Valid if the output is the control output and the "type of output"=1, that
is, the output is PWM or in case of 0 to 10Vdc output. The modulating
output can be limited to a relative minimum value.
Example of proportional control: "reverse" mode with St1 =20°C and
P1=1°C. If only one modulating output is used with a diff erential of 1°C,
setting this parameter to 20 (20%) will mean the output is only activated
when the temperature measured deviates more than 20% of the set
point, that is, with values less than 19.8°C.
Key
St1 Set point 1
OUT1 Output 1
B1 Probe 1
5.5.8 Maximum modulating output value (parameters
d37,d41,d45,d49)
Valid if the output is the control output and the "type of output"=1, that
is, the output is PWM or in case of 0 to 10Vdc output. The modulating
output can be limited to a relative maximum value.
Example of proportional control: "reverse" mode with St1 =20°C and
P1=1°C. If only one modulating output is used with a diff erential of 1°C,
setting this parameter to 80 (80%) will mean the output is only activated
when the temperature measured deviates more than 80% of the set
point, that is, with values less than 19.2°C. After this value the output will
remain constant.
Key
St1 Set point 1
P1 "Reverse" diff erential
d37 Maximum value of modulating output 1
OUT1 Output 1
B1 Probe 1
5.5.9 Enable modulating output Cut Off (parameter
c68)
This parameter is useful when needing to apply a minimum voltage value
for the operation of an actuator.
Enable operation with a minimum limit for the output PWM and 0 to 10
Vdc analogue outputs.
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OUT1
100%
d36=20%
0%
B1
P1
St1
P1 "Reverse" diff erential
d36 Min. value of modulating output 1
OUT1
100%
d37=80%
0%
B1
P1
St1