Detailed Electrical Design
Complete detailed electrical design for substations, plants and balance-of-plant — sized, coordinated and drawn to construction.
From single-line to issued-for-construction
NEWATT develops the full detailed electrical design package — single-line diagrams, schematics, sizing calculations and construction drawings — for power, renewable and industrial projects.
Every deliverable is coordinated with protection, earthing and civil design so the package that reaches site is consistent and buildable.
What this involves
Detailed electrical design is where a concept becomes a set of documents a contractor can actually build from. NEWATT produces the full package — single-line diagrams, protection and control schematics, metering and interlocking, load schedules and equipment sizing — for substations, renewable plants, BESS and industrial facilities.
Every item is sized and rated against the study results and the governing standards, and every schematic is coordinated with the protection philosophy, the earthing design and the physical layout. We design the LV, MV and HV distribution, the station auxiliary, DC and UPS systems, and the SCADA and automation architecture to IEC 61850.
The deliverable is a coordinated, issued-for-construction electrical package: drawings, schedules, calculations and specifications that are internally consistent and ready for procurement and construction — so the site team builds from a clean, complete set rather than working around gaps and clashes.
What we deliver
Single-line diagrams
We develop single-line diagrams from concept through issued-for-construction, covering every voltage level in the facility — incomer, distribution, sub-distribution and final circuits. Each SLD carries equipment ratings, cable sizes, protective device settings and cross-references to the load list, so the diagram stays the single source of truth as the design matures. Revisions are tracked and redlined so site teams and the client can see exactly what changed between issues, not just the final result.
Protection & control schematics
Protection and control schematics translate the SLD into wiring-level detail — relay connections, trip and close circuits, interlocking logic and alarm annunciation. We prepare schematic and wiring diagrams for every protection and control panel, cross-referenced to terminal numbers so panel builders and commissioning engineers can trace every circuit without guesswork. Schemes are checked against the protection coordination study before issue, so the wiring matches the settings the relays will actually be configured with.
Load lists & sizing
Every load in the facility is captured in a structured load list — connected load, demand factor, diversity and duty cycle — which drives transformer, switchgear and cable sizing throughout the design. We build the load list from process and mechanical inputs, apply the appropriate demand and diversity factors, and use it to size incomers, distribution boards and standby generation. The list is kept live through the design so late-stage load changes flow through to sizing automatically.
Construction drawings
Issued-for-construction drawings cover general arrangement, cable routing, panel layouts and installation details, prepared to a level of detail a contractor can build from without needing to ask the designer to fill gaps. We coordinate every drawing against the 3D model before issue, checking clearances, access and clash-free routing. Drawing packages are structured and numbered so site teams can find the right sheet quickly, with revision history that makes it clear exactly what changed and why.
Systems covered
LV / MV / HV distribution
We design the full distribution chain from incoming HV supply through MV switchboards down to LV distribution boards and final circuits, sizing switchgear, busbars and transformers at every level. Distribution architecture is chosen for the specific facility — radial, ring or looped — based on reliability requirements and fault levels, with selectivity checked between upstream and downstream devices. The result is a distribution system sized correctly the first time, not oversized for margin or undersized under real fault conditions.
Auxiliary, DC & UPS
Auxiliary power systems — station DC supply, battery banks and UPS — are sized for the actual protection, control and critical-load duty cycles they need to support, including worst-case discharge scenarios. We size battery capacity to IEEE 485 principles, select chargers and DC distribution, and design UPS systems for critical loads such as SCADA, protection relays and life-safety systems. Battery sizing calculations and single-line diagrams are issued together so the auxiliary system is fully traceable.
SCADA & automation
We design the SCADA and automation architecture that ties protection relays, meters and control systems into a single monitoring and control platform, specifying the communication protocol, network topology and I/O for each device. Point lists, network architecture drawings and functional descriptions are prepared so the SCADA integrator has everything needed to configure the system without repeated design queries. Automation logic for interlocking, sequencing and alarm handling is documented alongside the point list for a complete handover package.
Metering & interlocking
Revenue and check metering is specified and located to meet utility and grid-code requirements, with CT and PT ratios, accuracy classes and burden calculated for each metering point. We design mechanical and electrical interlocking schemes between switchgear, earthing switches and access points so unsafe switching sequences are physically prevented, not just procedurally discouraged. Metering schedules and interlock logic diagrams are issued as part of the protection and control package, cross-checked against the SLD.
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