Danfoss L66, User Manual

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The grey
side of the
ECL Card
Ex
tended ser
vic
e
The grey
side of the
ECL Card
Ex
tended ser
vic
e
Service parameter(s) 31-34 Service parameter(s) 35
32h 32i
31 Return temperature limitation - upper limit (X-axis)
Circuit Setting range Factory setting
I -60 ... 20 °C 15 °C
Set the outdoor temperature value (see drawing).
Set the outdoor temperature value (X coordinate)
for the upper limit.
(The corresponding Y coordinate is set in line 32).
32 Return temperature limitation - upper limit (Y-axis)
Circuit Setting range Factory setting
I 10 ... 110 °C 40 °C
Set the return temperature limitation referring to the outdoor
temperature value set in line 31 (see drawing).
Set the return temperature (Y coordinate) for the
upper limit.
(The corresponding X coordinate is set in line 31).
33 Return temperature limitation - lower limit (X-axis)
Circuit Setting range Factory setting
I -60 ... 20 °C -15 °C
Set the outdoor temperature value (see drawing).
Set the outdoor temperature value (X coordinate)
for the lower limit.
(The corresponding Y coordinate is set in line 34).
34 Return temperature limitation - lower limit (Y-axis)
Circuit Setting range Factory setting
I 10 ... 110 °C 60 °C
Set the return temperature limitation (see drawing).
Set the return temperature (Y coordinate) for the
lower limit.
(The corresponding X coordinate is set in line 33).
35 Return temperature influence - max. limitation
Circuit Setting range Factory setting
I / II -9.9 ... 0 ... 9.9 -2.0 / -2.0
Set the influence from the return temperature on the desired flow
temperature.
Set the influence of the max. return temperature
limitation (set in line 30 or lines 31-34).
Influence higher than 0:
The desired flow temperature is increased, when
the return temperature gets higher than the set
limit.
Influence lower than 0:
The desired flow temperature is decreased, when
the return temperature gets higher than the set
limit.
0
Influence
Max. limitation > 0
Return limit
Return temp.
Max. limitation < 0
Example
The return limit is active from 50 °C.
The influence is set to -2.0.
The actual return temperature is 2 degrees too high.
Result:
The desired flow temperature is changed by -2.0 x 2 = -4 degrees.
Normally, the setting in line 35 is lower than 0 in district heating
systems to avoid a too high return temperature.
Typically, the setting in line 35 is 0 in boiler systems because a
higher return temperature is acceptable (see also line 36).