Danfoss ECL Comfort 310 Operating Manual page 67

Operating Guide ECL Comfort 310, application P318
Speed control of charging pump
The charging pump P2 / V2 can be speed controlled by means of a
0 - 10 volt signal or a PWM (Pulse Width Modulation) signal. The
speed control signal, as 0 - 10 V, comes from the "Analog Out 2"
(terminals 60 and 56) on the ECA 32 or 35 module.
The speed control signal, as PWM, comes from the output "PWM
Out 2" (terminals 53 and 49) on the ECA 35 module.
When the charging temperature at S3 is less than 2 K below
the desired charging temperature, the speed will be decreased
gradually.
The control voltage / PWM is expressed as a % value and displayed
at the V2 symbol.
When the difference between charging temperature and desired
charging temperature becomes more than 2 K, the speed will be
decreased gradually.
The control voltage / PWM can be limited to a maximum and a
minimum % value.
Furthermore, the control signal can be reversed; this means the
higher the % value, the lower the speed.
Speed control of circulation pump
The circulation pump P3 / V3 can be speed controlled by means of
a 0 - 10 volt signal or a PWM (Pulse Width Modulation) signal. The
speed control signal, as 0 - 10 V, comes from the "Analog Out 3"
(terminals 61 and 56) on the ECA 32 or 35 module.
The speed control signal, as PWM, comes from the output "PWM
Out 3" (terminals 54 and 49) on the ECA 35 module.
A maximum return temperature (ID 13370) at S9 is set for the speed
control procedure.
The control voltage / PWM is expressed as a % value and displayed
at the V3 symbol.
When the return temperature gets lower than the set maximum
return temperature, the control voltage / PWM is gradually
increased in order to increase the speed of the circulation pump
more than the moment before. By this, the return temperature
aligns with the set maximum return temperature.
The control voltage / PWM remains on a stable value as long as
the return temperature corresponds to the set maximum return
temperature.
The control voltage / PWM can be limited to a maximum and a
minimum % value.
Furthermore, the control signal can be reversed; this means the
higher the % value, the lower the speed.
Danfoss District Energy VI.JM.Q3.02
DEN-SMT/DK 67