The Reset function block increases or decreases the value In1 depending on another value In2.
If In2 is within a specific range corresponding value of In1 is changed. A typical example is increasing a room temperature setpoint (In1) as a function of the outdoor temperature (In2).
If the outdoor temperature is between 75 - 90 °F ( 24 - 32 °C), for example, the room setpoint is raised by a specific value, by a maximum of 7 °F(4 °C).
Figure 1:Reset - Function Block |
Figure 2: Reset - Property Sheet |
Figure 3: Reset with Positive Delta |
Figure 4: Reset with Negative Delta |
Figure 5: Reset Function block to increase the cooling setpoint during summer
If the outside air temperature is more than 24°C (75°F), the room temperature setpoint of 23°C (73°F) is increased.
If the outside air tempprature >= 32°C (73°F), the maximum increase is reached (Fully Delta is added) and the room temperature setpoint is set to 27°C (80°F).
Input
Input Name |
Description |
Enable |
If the Enable is set to "false", Out = In1, that means, no offset is added. |
In1 |
In1 serves as the basis for the output value Out, which is either passed through or raised/lowered by Delta, depending on the amount of the value of In2. |
In2 |
In2 is a numeric value that decides whether and to what amount In1 gets an offset (Delta). |
X1 (In & Par) |
X1 refers to the value of In2. If In2 <= X1, In1 is not corrected, that means Out=In1 without additional offset. |
X2 (In & Par) |
X2 refers to the value of In2. If In2 >=X2, the full Delta is added to In1, i.e. Out=In2 + Delta. If In2 is between X1 and X2, a portion of 0 - 100% of Delta is added, that means Out = In1 + 0 - 100% * Delta. |
Delta (In & Par) |
Delta refers to In1. It is added to In1, if In2 at equivalent range. If In2 is between X1 and X2, a portion of 0 - 100% of Delta is added, that means Out = In1 + 0 - 100% * Delta. If In2 > X2, the entire Delta is added. |
Table 1:Inputs of Reset Function
Output
Output Name |
Description |
Out |
Output = Reset (input, sensor, 0%, 100%, reset amount). |
Table 2:Outputs of Reset Function
Parameter
Parameter Name |
Description |
X1 Par (In & Par) |
If X1 is "null", X1 Par is used instead of X1. If X1 Par set to "nan", it is treated like "null". |
X2 Par (In & Par) |
If X2 is "null", X2 Par is used instead of X2. If X2 Par set to "nan", it is treated like "null". |
Delta Par (In & Par) |
If Delta is "null", Delta Par is used instead of Delta. If Delta Par set to "nan", it is treated like "null". |
Out Save |
Master Sync Enabled: If you set it to "true" the last output will be set as output for one cycle after the controller restarts. The application can use it to return to the same state before the controller restart Out: To enable or disable the Out feature. |
Table 3:Parameters of Reset Function
Examples with °C
1. If the outdoor temperature In2 is < 24°C (X1 Par), the cooling setpoint In1 of 23°C is not increased. The new cooling value Out corresponds to the cooling setpoint In1.
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Figure 6: Reset Example 1 with °C
2. If the outside temperature In2 exceeds 24°C (X1 Par), the room cooling setpoint with 23°C (In1) is raised. The new cooling setpoint temperature Out = In1 + a percentage of Delta = 23.25°C.
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Figure 7: Reset Example 2 with °C
3. At the outdoor temperature of 28.16°C (In2), the cooling setpoint In1 = 23°C is increased by 2.08°C, Out = 25.08°C.
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Figure 8: Reset Example 3 with °C
4. At the outdoor temperature of 32.57°C (In2), the cooling setpoint In1=23°C is increased by the fully delta of 4°C, Out=27°C.
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Figure 9: Reset Example 4 with °C
Examples with °F
1. If the outdoor temperature In2 is < 75°F (X1 Par), the cooling setpoint In1 of 73°F is not increased. The new cooling value Out corresponds to the cooling setpoint In1.
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Figure 10: Reset Example 1 with °F
2. If the outside temperature In2 exceeds to 75°F (X1 Par), the room cooling setpoint with 73°F (In1) is raised. The new cooling setpoint temperature Out = In1 + a percentage of Delta = 73.52°F.
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Figure 11: Reset Example 2 with °F
3. At the outdoor temperature of 82.58°F (In2), the cooling setpoint In1 = 73°F is increased by 3.54°F, Out = 76.54°F.
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Figure 12: Reset Example 3 with °F
4. At the outdoor temperature of 91.54°F (In2), the cooling setpoint In1 = 73°F is increased by the fully delta of 7°F, Out = 80°F.
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Figure 13: Reset Example 4 with °F
Refer to General Description for general
information about IRMN4 Function Blocks.