SHD_EEI2: Shading energy efficiency indicator2, rule 2
Block SHD_EEI2 (FB804) calculates whether present shading supports cooling demand to the room and, thus, meets the condition for energy efficiency. The results are pending on the output.
Rule 2: Monitor blinds position at "unload".
Principle of operation
The block calculates at room load condition = unload (cooling demand), whether manually changing the blinds position prevents solar radiation to the room (heat load). The energy efficiency condition is evaluated and outputted.
IF | THEN | ||
Room load condition | Solar radiation | Blinds position | Energy efficiency condition |
"Unload" (cooling demand): [RThLdCndPrVal] = 2 | Available: [SolRdnCndPrVal] >= 2 | Up: [BlsCmdPrgsValh] < [BlsHgtOpnDsgn] | [Out] = 1 |
Not up: [BlsCmdPrgsValh] > [BlsHgtOpnDsgn] | [Out] = 0 | ||
None: [SolRdnCndPrVal] =1 | - | ||
"Load" (heat demand) [RThLdCndPrVal] = 1 | - | - | |
Blinds command present priority [BlsCmdPrPrio] <> 13 | |||
The following notes may help if the Green Leaf indication does not meet expectations:
- The Green Leaf indication is calculated from the results of energy efficiency of the disciplines used (HVAC, shading, lighting). Comply with the priorities of individual rules.
- Individual energy efficiency results are calculated based on user intervention as well as room conditions (outside air temperature, solar radiation, room loads, setpoints, ...).
- Changing room conditions can change independent of user interventions of the indicated energy efficiency results.
Example:
The blinds are manually closed, as the room load condition was "unload".
Result: SHD_EEI2: OUT = 0 (energy efficiency condition is met)
The room load condition changes to "load" since the outside temperature decreased in the interim. In this case, closed blinds prevent heat gains from solar radiation. Room load condition "unload" is also monitored and evaluated by block SHD_EEI1.
Result: SHD_EEI1: OUT = 1 (energy efficiency condition is not met). The Green Leaf indication changes to brown (no energy efficient operating state/condition).
Does not impact the result from SHD_EEI2: OUT = 0 (energy efficiency condition is met).
Inputs
Pin | E | Description |
BlsCmdPrgsValh |
| Progress value height for blinds command |
BlsCmdValid |
| Valid blinds command |
RThLdCndPrVal |
| Thermal room load condition present value 1 (Load) 2 (Unload) |
RThLdCndValid |
| Valid thermal room load condition |
SolRdnCndPrVal |
| Condition solar radiation present value 1 (None) 2 (Low) 3 (Medium) 4 (High) |
SolRdnCndValid |
| Valid solar radiation condition |
BlsCmdPrPrio |
| Blinds command present priority |
BlsHgtOpnDsgn | pax | Designed blinds height closed |
Outputs
Pin | E | Description |
Out |
| Output. 0 (No) Energy efficiency condition is met. 1 (Yes) Energy efficiency condition is not met. |
Input values
Pin | Description | Data type | Standard value | Engineering unit or text group | Min. | Max. |
BlsCmdPrgsValh | Progress value height for blinds command | REAL | 0.0 | % | 0.0 | 100.0 |
BlsCmdValid | Valid blinds command | BOOL | 0 | False, True |
|
|
RThLdCndPrVal | Thermal room load condition present value | INT | 2 | Load, Unload | 2 | 1 |
RThLdCndValid | Valid thermal room load condition | BOOL | 0 | False, True |
|
|
SolRdnCndPrVal | Condition solar radiation present value | INT | 1 | None, Low, Medium, High | 1 | 4 |
SolRdnCndValid | Valid solar radiation condition | BOOL | 0 | False, True |
|
|
BlsCmdPrPrio | Blinds command present priority | INT | 16 | BA present priority for SystemOne | 0 | 17 |
BlsHgtOpnDsgn | Designed blinds height closed | REAL | 10.0 | % | 0.0 | 100.0 |
Output values
Pin | Description | Data type | Standard value | Engineering unit or text group | Min. | Max. |
Out | Output. | BOOL | 0 | No, Yes |
|
|
Process response
Standard (see General rules and information).
Troubleshooting
Standard (see General rules and information).