5.4 Flow / power limit
A flow or energy meter can be connected (M-bus signal) to the ECL
controller in order to limit the flow or consumed power.
The flow / power limitation can be based on the outdoor
temperature. Typically, in district heating systems a higher flow or
power is accepted at lower outdoor temperatures.
The relationship between the flow or power limits and the outdoor
temperature is set in two coordinates.
The outdoor temperature coordinates are set in 'High T out X1'
and 'Low T out X2'.
The flow or power coordinates are set in 'Low limit Y1' and 'High
limit Y2'. Based on these settings, the controller calculates the
limitation value.
When the flow / power gets higher than the calculated limit, the
controller gradually reduces the desired flow temperature to obtain
an acceptable max. flow or power consumption.
Flow / power limitation
High limit Y2
Low limit Y1
Outdoor temp.
Low T out X2 High T out X1
Flow / power
limitation
Limit
Desired flow
temp.
Time
If the ‘Adapt. time’ is too high, there is a risk of unstable control.
MENU > Settings > Flow / power limit
Actual (actual flow or power)
The value is the actual flow or power based on the signal from flow / energy
meter.
MENU > Settings > Flow / power limit
Limit (limitation value)
1x111
This value is in some applications a calculated limitation value, based on the
actual outdoor temperature.
In other applications the value is a selectable limitation value.
See Appendix “Parameter ID overview”
VI.GU.T2.02
© Danfoss | 2017.09 | 79
Operating Guide ECL Comfort 310, application A333
