If impedance, tap range or cooling class is wrong, the first turbine to close onto the bus can cause a voltage dip that drops sensitive loads, or overload a winding that then fails months later. Either way you face downtime, a long-lead replacement and a delay you did not budget for.
USP&E as Your Guide for MV Yard Upgrades
Industrial buyers who search “Cat genset” often need a power station: civil works, fuel farm, MV/HV yard, protection, paralleling, control room, and an O&M plan. catgenset.com exists to make that leap explicit. Where product-led twin pages catalogue machines, this guide explains how USP&E turns packaged gensets and gas turbines into stations that survive frontier dust, utility grid codes, and industrial step loads.
Treat the Transformer as the Gate to Growth
List every transformer and MV feeder on site with its rating, impedance, tap changer type, cooling class and loading history. Then model the combined fleet: Cat gensets plus the new turbine, at peak load and during a turbine trip. That study shows whether you need a new step-up unit, a larger secondary or separate buses for the two fleets.
Impedance matters in both directions. Too low and fault levels exceed your switchgear rating; too high and voltage regulation suffers when large motors start. Pick a value that keeps both within limits, and confirm the tap range covers the grid or plant voltage you will actually see.
Plan Inrush, Energisation and Cable Ampacity
Energising a large transformer pulls inrush current that can trip upstream protection or dip the bus your Cat gensets are holding. Decide the energisation sequence early: from the turbine side with a soft voltage ramp, from a strong grid connection, or with point-on-wave switching. Write it into the commissioning plan rather than discovering it on the day.
MV cables need the same honesty. Derate for burial depth, soil thermal resistivity, grouping and ambient temperature, and leave spare ducts. A remanufactured GE Frame 6B or other used or new gas turbines can arrive faster than a replacement cable run, so the cable plan should be ready when the machine is.
Leave Space for the Next Blocks
Start with an accurate model of what you have: every Cat genset, transformer, cable run, breaker and relay setting on the single-line diagram, verified in the field rather than copied from old drawings. Then add the proposed gas turbine generators and calculate fault levels for every credible operating case, including all units online and maintenance configurations.
Construction yards treat generators as commodities until a tower crane, batch plant, or camp kitchen goes dark mid-pour. Cat genset temporary power must be sized for simultaneous motor starts, night lighting, and office UPS loads — then packaged for mud, dust, and neighbour acoustics. USP&E approaches temporary fleets with the same Extreme Ownership as permanent plants: matched packages, fuel discipline, and a path to permanent COD if the project grows. Not an official Caterpillar dealer — brand-agnostic lifecycle partner only.
Proof from recent work
Mining · Tanzania
Perseus Mining, Nyanzaga Gold Project
USP&E supplied 28 Cummins KTA50 containerised gensets for the Nyanzaga Gold Project in Tanzania.
Mining · Mali
Barrick Gold, Loulo-Gounkoto
USP&E refurbished the 104 MW power station, rebuilding more than 80 MW of Caterpillar CM32 engines and adding new zero-hour capacity.
Read the case study ›Data centres · USA
Major US hyperscale developers
USP&E refurbished 7 GE Frame 6Bs to zero hours in-house for major US hyperscale developers.
Your path from first call to reliable power
Construction temporary power and rental fleets often park Cat-compatible packages beside offices, camps, and haul roads. Acoustic success is then geometry: barriers, orientation of louvres away from receptors, and night-time load discipline. Soft ties to weak utilities do not excuse noisy idle banks. Where packages later demobilise, acoustic barriers should not strand civil CapEx — design demountable where the schedule says so. Cross-link construction temporary power and Cat genset rental fleets when the duty is temporary.
- Map Cat genset transformer ratings, MV cable ampacity, and which duties can move to gas turbine generators.
- Re-run impedance, tap, and protection reviews; integrate SCADA, training, spares, and O&M in one matrix.
Common questions
Why revisit transformers when adding a gas turbine beside Cat gensets?
USP&E revisits transformers because a gas turbine changes load, fault levels and energisation conditions on your MV yard. A unit sized for diesel may overheat, limit output or cause voltage dips when the turbine closes onto the bus, so the study comes before the purchase order, not afterwards.
Can a remanufactured GE Frame 6B share a secondary with Cat gensets?
USP&E can design a shared secondary when transformer rating, impedance, protection and voltage control all allow it. In many cases a separate step-up transformer for the turbine is cleaner. The decision comes from a combined load flow and fault study using your actual transformer data and loading history.
How do you manage transformer inrush on a mixed fleet?
USP&E plans transformer energisation as a written sequence, choosing whether to energise from the turbine with a voltage ramp, from a stronger source, or with controlled switching. Protection settings are checked against expected inrush so upstream breakers do not trip and the Cat gensets keep holding the essential bus.
Why owners choose USP&E
USP&E is a full-service engineering, EPC and O&M company, not a broker. One team designs, builds and runs your plant, so nothing falls between contracts.
Is your fleet putting uptime at risk?
Tell us your load, fuel and timeline. A USP&E engineer will come back with options for Cat Genset projects, not a sales pitch.