System Interface Definitions

Purpose

System interface definitions establish the precise points where one system, module, or scope of work ends and another begins. They are essential for coordinating multi-vendor projects, managing factory-to-site transitions, and ensuring that integrated systems function correctly when individual components are brought together on site.

This document defines the standard interface specifications used across all GridCore deployment models. Each interface is specified in terms of physical connection details, performance requirements, testing criteria, and documentation deliverables.

Electrical Interfaces

• Utility Service Entrance: Metering point, protection device ratings, grounding requirements, and utility coordination settings.
• Transformer Secondary: Voltage, ampacity, phase configuration, neutral treatment, and cable termination specifications.
• UPS Output: Voltage regulation, frequency stability, harmonic content limits, and transfer time requirements.
• Inter-Module Bus: Bus rating, connection hardware, torque specifications, and thermal monitoring provisions.
• Rack PDU Input: Connector type, circuit rating, monitoring protocol, and branch circuit protection.

Mechanical Interfaces

Mechanical interfaces cover fluid connections (chilled water, condenser water, refrigerant), air handling connections, and structural mounting interfaces.

• Chilled Water Supply/Return: Pipe size, flange rating, temperature differential, flow rate, pressure drop budget, and glycol concentration.
• Condenser Water/Glycol Loop: Similar to chilled water with additional heat rejection capacity specification and ambient design conditions.
• Air Handling Connections: Duct size, static pressure, airflow rate, filter specifications, and damper control interface.
• Structural Mounting: Anchor bolt patterns, load ratings, vibration isolation requirements, and seismic restraint specifications.

Controls and Monitoring Interfaces

Controls interfaces define how monitoring and control systems communicate across module and system boundaries.

• BACnet IP Network: Device instance ranges, object naming conventions, polling intervals, and COV subscription requirements.
• Modbus TCP/RTU: Register maps, data types, polling rates, and exception handling.
• SNMP: MIB definitions, community strings, trap destinations, and polling intervals for network equipment monitoring.
• Dry Contact Points: Contact type (NO/NC), voltage rating, current rating, and function assignment for inter-system status and alarm signals.

Telecom Interfaces

• Fiber Optic: Cable type (OS2/OM4), connector type (LC/MPO), port count, and fiber management requirements.
• Copper Network: Cable category, connector type, patch panel specifications, and cable pathway provisions.
• Carrier Demarcation: Meet-me room provisions, carrier cage specifications, and cross-connect procedures.

Factory-to-Site Handover

Each interface specification includes a clear delineation of factory scope (what is built, tested, and documented before shipping) and site scope (what is connected, commissioned, and verified during installation). This boundary definition reduces schedule ambiguity and change-order risk by ensuring both factory and site teams understand their responsibilities before work begins.

Acceptance Criteria

Every interface includes defined acceptance criteria covering visual inspection requirements, functional test procedures, measurement tolerances, and documentation deliverables. Acceptance testing follows a structured sequence from individual component tests through inter-system integration verification to full facility commissioning.