HT/LT Electrical Contractor for Industrial Plants

What to have ready

• Connected-load list and estimated maximum demand
• DISCOM sanctioned load, or the status of the load application
• Single-line diagram if one exists, and the site plan showing the substation location
• Process equipment list with ratings and starting characteristics
• Backup power requirement — which loads are critical, and for how long
• Power-quality needs such as harmonic limits or power-factor targets
• Details of the existing installation if this is an expansion
• Target energisation date

What drives the cost

• Sanctioned load and supply voltage — an HT connection adds a substation, metering and CEIG scope
• Transformer and DG capacity, and whether DG sets must synchronise
• Number and rating of panels, and the level of protection and metering specified
• Cable lengths and sizes, and copper versus aluminium conductors
• Bus duct versus cable for high-current risers
• Lighting type and target lux levels by area
• Soil resistivity — dry or rocky ground needs more electrodes and treatment to reach the earthing values required
• Redundancy such as dual feeders, automatic transfer or ring mains

What drives the timeline

• DISCOM load sanction and metering — the connection agreement gates the programme
• CEIG drawing approval, which must precede substation construction
• Transformer and switchgear lead times
• Civil readiness of the substation, cable trenches and DG foundations
• Inspection scheduling and shortfall closure before energisation
• Coordination of cable routes with other trades

Approvals that usually apply

• DISCOM load sanction and connection agreement
• CEIG / Electrical Inspector drawing approval and inspection for HT installations, and for the classes of LT installation each state notifies — commonly DG sets, lifts and larger buildings
• State pollution-board consent for DG sets, with CPCB-compliant acoustic enclosures and emission norms
• Licensed electrical contractor and supervisor credentials, which the inspectorate checks at submission

Standards and codes we design to

• IS 732 wiring
• IS 3043 earthing
• IEC 61439 panels
• IS/IEC 60947
• CEA Regulations
• NBC 2016 Part 8

Maintenance after handover

Transformer oil testing, thermographic scanning of panels and joints, relay and protection testing, earthing resistance measured and recorded before each monsoon, DG servicing and load tests, APFC capacitor health checks, and lux-level verification — plus the periodic CEIG inspection where the installation class requires it.

See our AMC and maintenance scope →

Mistakes we see most often

• Applying for sanctioned load without a proper load estimate, then under- or over-sanctioning
• Starting substation civil work before the CEIG drawing approval
• Treating earthing as an afterthought rather than a designed and measured system
• No discrimination study, so an upstream breaker trips before the one nearest the fault
• Running cables without derating for grouping, ambient temperature or installation method
• Ignoring power factor until the penalty appears on the bill
• Adding DG sets without deciding the AMF or synchronising scheme first