[SplyHw22] Supply chain hot water, data exchange with other plants, with valve position evaluation, heating curve

Program block, name / node subtype: [SplyHw22] Supply chain hot water, data exchange with other plants, with valve position evaluation, heating curve

Library hierarchy: Coordination

Family: SplyHw

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Diagram

Configurator

info

Program blocks are stored in the library without I/Os. Use the auto-create and auto-connect functions to create I/Os and/or to connect them to the interface blocks, e.g., R_A, CMD_B. Alternatively, take the I/Os from the folder containing the predefined I/Os in the library and/or from the plant and connect them to the interface blocks.

Function

SplyHw22 connects one or more hot water consumers, e.g., air handlers, to the heating plant.

The most important functions in the program block are:

  • Heating demand collection and evaluation
  • Hot water temperature setpoint calculation and its correction based on valve position evaluation of the consumers
Mandatory elements

Name

Description

Type

Alarm / Notification class

Trend / Type

SpHReq

Setpoint for heating request

ACalcVal: Analog calculated value

N/A

N/A

HReq

Heating request

BCalcVal: Binary calculated value

N/A

N/A

Optional elements

Name

Description

Type

Alarm / Notification class

Trend / Type

SpHReqMin

Minimum setpoint heating request

ACnfVal: Analog configuration value

N/A

N/A

Hcrv

Heating curve

[Hcrv21] Heating curve, flow temperature setpoint calculation, with HCRV

N/A

N/A

Dmd(1)

Demand (1)

Chart

N/A

N/A

Dmd(2)

Demand (2)

Chart

N/A

N/A

Dmd(3)

Demand (3)

Chart

N/A

N/A

Dmd(4)

Demand (4)

Chart

N/A

N/A

Dmd(5)

Demand (5)

Chart

N/A

N/A

Dmd(6)

Demand (6)

Chart

N/A

N/A

Dmd(7)

Demand (7)

Chart

N/A

N/A

Dmd(8)

Demand (8)

Chart

N/A

N/A

Further options

Description

Setpoint correction for flow temperature based on valve position evaluation

Elements that belong to this option:

Setpoint correction for lower flow temperature | ACnfVal: Analog configuration value

Setpoint correction for higher flow temperature | ACnfVal: Analog configuration value

Further information

Heating demand collection and evaluation

SplyHw22 receives binary hot water demand signals [HwDmd1...n], [WarmUpDmd1...n] from consumers, and calculates binary values for the heating request and warm-up request output pins [HReq], [WarmUpReq]. If at least one hot water demand signal or warm-up demand signal is True, the corresponding output pin(s) is True.

Hot water temperature setpoint calculation and its correction based on valve position evaluation of the consumers

SplyHw22 receives valve position values from consumers (VlvPosVal1...n), and calculates a representative valve position value [HwVlvPosEvl]. [HwVlvPosEvl] is the average of valve positions that:

  • Are ≥ 10 %
  • Have no disturbances
  • Are from consumers with an active hot water demand signal

A linear function (configurable) uses [HwVlvPosEvl] to calculate a hot water supply temperature setpoint correction value between SpCorrTFlHi and SpCorrTFlLo:

Key

SpCorrTFlHi

Setpoint correction for higher flow temperature

SpCorrTFlLo

Setpoint correction for lower flow temperature

HwVlvPosEvl

Supply chain hot water valve position evaluation

The calculated setpoint correction value is added to the base setpoint (the base setpoint is calculated by applying a heating curve (see figure) based on outside air temperature [TOa]). The result is the hot water heating request setpoint value [SpHReq] (chart output pin).

Key

SpTFlDs

Flow temperature setpoint for design outside temperature

SpTFlHi

Flow temperature setpoint for high outside temperature

TOaDsgn

Design outside temperature

TOaHi

Outside temperature high

The suggested setpoint value [SpHReq] can be delivered to the heating plant or other coordinator(s) (SplyChw23).