EN - iSii compact: How to set up the Curtain control

EN - iSii compact: How to set up the Curtain control

  
Question

How to set up the Curtain control?

 Answer 

The curtain can be closed for two purposes:
  1. To save energy (energy function)
  2. To protect the crop against too much radiation from the sun (shading function)
The setpoints for curtains can be found as follows:

 

Energy curtain


The curtain is closed as energy curtain under 3 conditions:
  1. Outside temperature is too low 
  2. Greenhouse temperature is too low
  3. The period is released
If the curtain is closed as energy curtain, a crack can be set.



If the outside temperature measurement is below 2 °C, condition 1 is met. 

 

If the greenhouse temperature measurement is below 17 °C (20-3), condition 2 is met.
The condition can be switched off by setpoint "temperature difference: release" to 40 °C.

 

Between sunset and 1 hour after sunrise, condition 3 is met.
 


The crack in the curtain is 2%.

Example 1:

Close the energy curtain if the outside temperature during the day is below 2 °C  and during the night below 12 °C.

 

Example 2:

Crack in the energy curtain of 2% if the measured RH in the greenhouse reaches 95%.


 
 

Shading curtain

The curtain is closed as shading curtain if the measured radiation is too high.

 

 

As soon as the measured radiation is higher than 700 W/m2, the shading curtain becomes active. The curtain is set to minimum position, in this case 80%.
The P-band is used to further close the crack. At 1000 W/m2 (=700+300), the curtain is at its maximum position, in this case 100%.

Example: 

The calculated position of the curtain with increasing radiation.

Radiation W/m2
Calculated curtain position %
650
0
700
80
800
87
900
94
1000
100
1050
100