Equipment Interrelationships using the System class

[connorjcantrell]

Overview

This issue addresses the Chiller unit, emphasizing its integration within four interconnected systems:

1. Condenser Water System (CWS)
2. Refrigeration System (self contained within the Chiller)
3. Chilled Water System (CHWS)
4. Electrical System

Equipment Overview

• Cooling Tower: Part to the Condenser Water System.
• Chiller Components:
  • Condenser Heat Exchanger: Part of both CWS and Refrigeration System.
  • Evaporator Heat Exchanger: Part of both CHWS and Refrigeration System.
  • Metering Device/Expansion Valve: A critical component in the Refrigeration System.
  • **Compressor: Core part of the Refrigeration System and perhaps Electrical System
    • Variable Frequency Drive (VFD): Core component of Refrigeration System and Electrical System.

Differentiating multiple 'Feeds'/'IsFedBy' Relationships

The current challenge is accurately representing 'feeds' and 'isFedBy' relationships from the perspective of the Chiller. For example, the phrases "Condenser HX feeds Cooling Tower" and "Condenser HX feeds Metering Device" does not specify that these are two entirely different systems (and substances).

Proposed Solution: Use 'System' Class for Contextualizing Relationships

To resolve this ambiguity, I propose using the System class as a "local scope". By classifying equipment/ and components under specific systems, we can infer the nature of their interactions. For instance:

• In the CWS, the relationship "Condenser HX feeds Cooling Tower" would imply they are part of the CWS, since both the Condenser HX and Cooling Tower belong to the CWS.
• In the Refrigeration System, a similar 'feeds' relationship between the Condenser HX and the Metering Device would imply they are part of the Refrigeration System, since both the Condenser HX and Metering Device belong to the Refrigeration System.
• In the Electrical System, the relationship "VFD feeds Compressor" would imply they are part of the Electrical System, since both the Compressor and VFD are part of the Electrical System.

With this approach, we can begin adding unique properties to systems, such as an Electrical Systems voltage rating (e.g. 450V), a Refrigeration Systems refrigerant type (e.g. R22, R410a), or a Chilled Water System's piping configuration (parallel).

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In the most recent consortium meeting, we were discussing how this might be represented in 223p. I'm curious to get other perspectives on how to represent these equipment relationships.

Thanks,
Connor