Bericap 2500 kVA Kiosk Substation Case Study: from Survey to Energization

Quick project summary – Bericap 2500 kVA

The project named Bericap is a substation with a reported total capacity of 2500 kVA and construction milestones recorded from 28/12/2022 to 28/03/2023; other detailed information is included only when publicly verifiable sources are available. ^[0][0]

According to aggregated data, the construction start and energization/completion milestone are 28/12/2022–28/03/2023; however, information such as the investor name, contractor, exact site location and transformer connection diagram are not currently cited in public sources and therefore marked as “not disclosed” in the public dossier.

Main construction scopes (listed according to applicable industry categories) include:

• Substation foundation work and civil works for transformer plinths.
• Transformers totaling 2500 kVA — type and primary/secondary connection diagrams: not disclosed in currently available public documents.
• Distribution boards (MSB/DB) and control panels, power and control cabling for primary feeders.
• Earthing system and lightning protection.
• Capacitor bank/capacitor panel — listed only if implemented; in public records it is not yet clearly determined whether the capacitor bank was installed.

Regarding acceptance, energization and connection procedures: energization acceptance is organized and signed off by the investor’s acceptance committee; prior to connection there must be an acceptance report, the results of required tests and confirmation of the connection point from the distribution utility (EVN or the local distributor). During on-site survey, the construction/testing team must verify actual operating parameters at the connection point before energization.

Practical caution: no contract values or individual names in acceptance reports are included in the document without public sources; to complete the project dossier the next steps are to collect acceptance/energization minutes, connection confirmations from the distribution utility and any public multimedia (video/press) that reference the acceptance milestone for cross-checking.

Context and power requirements for an FDI factory at Long Hau IP

A 2500 kVA substation is suitable for FDI factories in industrial parks with high peak loads, especially installations with many motors, compressors and automated production lines. ^[9][13]

Technically, 2500 kVA meets the needs of medium–large load groups in an industrial park where peak loads must be sustained and reserve capacity is required to limit voltage drop at the supply point. During factory surveys, important input data include load profiles (hour/minute), power ratings of motors/compressors, and expansion plans over 1–3 years to determine reserve factors and LV configuration.

On-site checks and minimum criteria before sizing include:

• Load profile by hour/minute and major loads (list of motors, ratings, power factor).
• Expansion plans for 1–3 years to determine reserve capacity requirements.
• Distance to the medium-voltage network, existing supply voltage (6–22 kV) and the distribution utility’s capability for connection.
• Substation footprint, environmental conditions (humidity, corrosion) and earthing requirements.

Quick comparison of substation types: kiosk/prefab substations occupy less area and install faster, suitable where space is limited in an industrial park; traditional substations (AIS/GIS) require larger footprints and longer construction times but are preferable when large expansions or complex MV routing is needed.

When preparing medium-voltage connection documentation, follow EVN’s new electricity service guidelines; in practice at Long Hau IP, customers must coordinate submitting documents to the utility, determine the connection voltage (6–22 kV) and provide technical documentation for the utility’s capacity assessment. During maintenance and acceptance, inspection responsibilities are split between the substation supplier and the utility for the energization stage.

Insufficient capacity leads to voltage drop at loads, transformer overload, reduced productivity and increased risk of equipment failure; additionally, low power factor raises losses and may trigger corrective measures from the utility. Therefore, plan for capacitor banks to improve power factor and lower operational losses.

Safety requirements include proper design of the earthing and lightning protection system for a substation located in an industrial park, and performing installation acceptance and pre-energization tests: short-circuit impedance measurement, insulation resistance tests and earth resistance measurement. Operational caution: without site surveys and load profiles, sizing decisions may result in wrongly sized equipment and operational risks.

Brief conclusion: collecting load profiles and surveying the site and distance to the MV network are mandatory next steps to perform detailed sizing, choose between a kiosk or traditional substation and finalize the connection dossier with the utility.

Field survey and 22 kV connection conditions

The 22 kV connection point was identified as the Long Hau 110/22 kV substation, with the branch circuit managed by Can Giuoc Power Company. The surveyed connection route is a 3×70 mm² underground cable (noted as 24 kV/22 kV) and must be cross-checked with route dossiers before construction. ^[0][0]

On site, check pole positions, cable ducts, manholes and distance to other infrastructure such as water supply/drainage and communications conduits. Measure and record coordinates of the connection point, elevations, road surface condition and photograph the existing state to prepare a complete survey report.

Minimum checks and acceptance items for the underground portion include:

• Review route documents and previous acceptance minutes; reconcile positions of ducts, conduits and technical corridor markers.
• Record coordinates & elevations of the connection point, photograph excavation pits and joints; archive in the survey minutes.
• Determine burial depth, sheath and insulation requirements per EVN/TCVN regulations (cite documents when official dossiers are available).
• Check temporary drainage measures for excavations to avoid water pooling that could affect underground cables.
• Underground acceptance: insulation testing (megger), joint inspection (kit/epoxy/solder per dossier) and prepare MV acceptance minutes as required by the power utility.

Construction operations in an industrial park must minimize traffic impact. Work should be staged, performed during off-peak hours or at night, and have safety barriers per the industrial park management’s rules.

Operational caution: do not cut through hot-mix asphalt without approved restoration plans; all cutting must include a restoration proposal meeting industrial park standards and local regulations. Before working on MV circuits, isolate circuits using mechanical switches (MC), lockout, post warning signs and apply temporary earthing.

Coordinate early with Can Giuoc Power/EVN SPC on shutdown schedules, load transfer measures and energization schedules. For acceptance, prepare photo documentation, route diagrams, the survey report and an acceptance request to finalize energization timing and bring the connection into operation.

Kiosk 2500 kVA substation design (transformer, MV/LV configuration, capacitor bank)

The kiosk 2500 kVA design prioritizes a Siemens dry-type transformer combined with a 1000 kVAr capacitor bank to target a power factor of approximately 0.95–0.98 and reduce reactive power in the distribution system. On site, a dry-type transformer is suitable for enclosed kiosks or indoor locations because it lowers fire risk compared with oil-filled transformers and reduces fire protection requirements. ^[2][1]

Protection and distribution equipment are arranged so that the main ACB and MSB/MDB 4000 A sit on the secondary side immediately after the transformer, enabling fast isolation and protection of the main distribution block during factory surveys. Verify available short-circuit capacity at the connection point and protection coordination to ensure the 4000 A ACB withstands fault conditions and is compatible with protection relays.

The 1000 kVAr capacitor bank size is selected to compensate reactive power toward ~0.95–0.98; compensation strategy can be staged or automatic (AVR/PLC + capacitor switching) to follow load changes. In practice, measure existing reactive power and harmonic spectrum before installing capacitor banks because overcompensation or compensation in the presence of high harmonics can cause resonance and adverse effects on the system.

Earthing and lightning protection must comply with current guidelines; transformer neutral earthing and a common earthing grid for the kiosk are mandatory for safe operation. Environmentally, dry-type transformers require ventilation and protection from moisture and dust; kiosk dimensions must ensure clearance for insulation and heat dissipation, and include vents or forced ventilation if necessary.

Pre-energization checks and acceptance tests should include the following practical steps after installation:

• Equipment documentation check: catalogues, factory test reports, and standard certificates for the transformer and capacitor bank.
• Mechanical and installation inspection: safety clearances, anchor bolts, door interlocks and kiosk ventilation.
• Electrical tests: insulation resistance measurements, no-load tests and transformer ratio tests; earthing resistance and earth grid continuity tests.
• Protection acceptance: verify relay settings, ACB/MSB coordination, capacitor switching function tests and interlocks.
• Coordinate energization with EVN/local distribution company before applying primary grid power.

On-site surveys are required to validate input data before producing construction drawings and an acceptance program: especially the short-circuit level at the connection point, specific primary/secondary voltages, load profile over time and harmonic spectrum. After obtaining real data, finalize protection settings, select the correct 4000 A ACB/MSB and define a safe compensation strategy to avoid resonance.

22 kV underground cable construction using robotic roadheader and MV connection infrastructure

Robotic roadheader is a horizontal drilling method to install conduit and pull a 3×70 mm2 24 kV underground cable through hot-mix asphalt, replacing open trenching in many industrial park cases. On site, this method reduces lane closures and the risk of pavement structure damage compared with open-cut trenches. ^[0][0]

The construction process typically includes corridor survey, construction permits, preparation of launch and reception pits, horizontal drilling across the road, cleaning the conduit, cable pulling, and road surface restoration. When surveying at the factory, collect roadbed drawings, pavement layer details and positions of existing underground infrastructure to determine the drilling path and reception pit locations.

1. Site survey and construction permit, coordinate temporary traffic flow with authorities.
2. Prepare launch/reception pits: excavate adequate size, implement measures against collapse and provide drainage.
3. Perform horizontal drilling with a robotic/horizontal directional drilling rig; bore across the road and clean the conduit.
4. Pull cable through the conduit, apply temporary earthing and safety measures while handling MV cables.
5. Inspect the conduit, perform insulation checks on the cable and restore the road surface per procedure.

Drilling equipment selection criteria include the drill head diameter compatible with conduit and cable cross-section, maximum pull force for 3×70 mm2 cable, steering capability for horizontal drilling, and ability to operate in asphalt or mixed soils. During works, take measures against sinkage or voids if groundwater pockets or dense aggregate layers are encountered under the road.

• Verify pavement structure and existing underground utilities before drilling.
• Ensure temporary earthing and electrical contact protection for workers when pulling MV cables.
• Schedule work during off-peak hours or nights, provide signage and a traffic safety team on site.

For acceptance and post-construction checks, inspect cracks or subsidence on the road, conduit straightness/free of kinks, and the cable insulation parameters after installation. For MV connection acceptance, coordinate closely with EVN or the grid operator to organize safe switching operations and meet connection requirements.

Operational caution: incorrect drilling techniques may compress or kink the conduit or damage pavement structure; have contingency plans to switch to mechanical cutting or core-drilling if thick concrete or rock layers are encountered. Road restoration quality and site aesthetics are non-negotiable acceptance criteria in the industrial park at the end of works.

Kiosk installation, LV cable pulling, testing, acceptance and energization; factory checklist

Completed installation included a Siemens dry-type transformer 2500 kVA, 3P ACB 4000 A 100 kA, MDB/MSB 4000 A, an approximate 1000 kVAr capacitor bank, nearly 1000 m of 300 mm2 LV cable and five MV underground cable terminations. ^[0][0]

On site, the basic principles for dry-type transformers are to check placement, foundation, ventilation and safety clearances before lifting; the foundation, anchor points and kiosk openings must allow airflow and avoid heat accumulation. During factory surveys verify minimum clearances around the transformer, access for equipment transport, lifting schemes and anti-rolling measures, while controlling handling to avoid mechanical shock to windings.

Pulling 300 mm2 LV cables requires appropriate conduits, cable trays or steel conduits, labeling at each cable end and records of joint locations. For pull force limits and jointing, refer to the cable manufacturer’s catalogue and requirements; during on-site works and acceptance perform continuity and insulation checks before and after pulling. Influencing factors include the nearly 1000 m length, number of bends, underground joints and transition points.

Pre-energization test procedures include mechanical inspection, insulation resistance measurement (Megger/IR), earth resistance testing, phase separation tests and functional testing of ACBs. The capacitor bank must have its connections, controller and automatic switching functions tested. For relay/ACB commissioning, prepare a clear test list, record step-by-step minutes and archive test results (Megger, IR, earth measurement, ACB functional tests).

Acceptance coordination typically assigns responsibilities: the investor provides equipment documentation and approves the energization plan, the contractor performs installation and tests, and the utility/testing unit (EVN) carries out inspections/energization as required. Energization acceptance must include minutes, test results and equipment receiving documents; note that the internal energization milestone 28/03/2023 is declared internally — project minutes are required for verification.

• Preparation checklist for the investor when requesting quotations:
  • acceptance/receiving dossier (PO, factory certificates, equipment serial numbers);
  • list of main equipment and single-line diagram;
  • as-built drawing expectations for cable routes, joint locations and earthing points;
  • energization plan with isolation procedures, lockout/isolation requirements and coordination requests with the utility;
  • lifting and cable-pulling safety plan, overload protection devices;
  • proposed acceptance schedule and list of test instruments required.

Operational risks and safety requirements include verifying the earthing system before energization, applying safety labels, performing lockout/tagout (LOTO) procedures during works, and having emergency contact arrangements with the utility in case of isolation or incidents. Legally and operationally, note requirements for measuring and trading reactive power when capacitor banks are present according to relevant circulars; after energization perform trial runs, load monitoring and power quality checks following EVN’s power facility testing procedures.

To finalize construction method, acceptance schedule and accurate quotations, perform an on-site survey, provide detailed cable route drawings, equipment catalogues and any acceptance/energization minutes if available; missing documents will require recalculating cable pulling volumes, number of joints and earthing schemes before signing contracts.