blockDisableDedicated
Pump disable for plants with dedicated primary pumps
Information
The pump is disabled when the associated plant equipment is disabled and:
-
if the equipment has a flow request network point
(
have_req=true): either the equipment has been proven off fordtOffor is not requesting flow. -
otherwise (
have_req=false): the equipment has been proven off fordtOff.
When the flow request point is available, the default value for the pump
disable delay dtOff is increased from 3 min
to 10 min to ensure that flow is not cut off too soon.
Details
Used in Guideline 36 for disabling dedicated primary pumps in chiller and boiler plants.
The enable signal u1 is yielded by the staging event sequencing logic.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | have_reqFlo | false | Set to true if plant equipment provides flow request point via network interface |
| Real | dtOff | if not have_reqFlo then 3*60 else 10*60 | Runtime with lead equipment proven off before disabling |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | u1ReqFlo | Flow request from equipment | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | u1 | Enable signal from system enable logic | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | u1Equ | Equipment enable signal | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | u1Equ_actual | Equipment status | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput | y1 | Lead pump enable signal |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Logical.Latch | lat | Clear enable signal if disable conditions are met | |
| Buildings.Controls.OBC.CDL.Logical.Not | dis | Return true if lead equipment is disabled | |
| Buildings.Controls.OBC.CDL.Logical.Not | off | Return true if lead equipment is proven off | |
| Buildings.Controls.OBC.CDL.Logical.Sources.Constant | fal | Placeholder constant | |
| Buildings.Controls.OBC.CDL.Logical.Or | offOrNotReq | Return true if lead equipment proven off OR not requesting flow | |
| Buildings.Controls.OBC.CDL.Logical.Timer | timOff | Return true if lead equipment is proven off for specified duration | |
| Buildings.Controls.OBC.CDL.Logical.And | disAndOffOrNotReq | Return true if lead equipment disabled AND (proven off OR not requesting flow) | |
| Buildings.Controls.OBC.CDL.Logical.Edge | edg | Trigger true signal when disable conditions turn true | |
| Buildings.Controls.OBC.CDL.Logical.Not | noReq | Return true if no flow request | |
| Utilities.Initialization | ini | Force false clear signal at initial time |