Load Banks – Resistive, RLC & RCD Load Banks from 30kW to 2500kW

A load bank applies a controlled, adjustable electrical load to a generator, UPS, or power source so its real performance can be verified — not just its standby readiness. DKS Enterprises supplies resistive, RLC, and RCD load banks engineered for generator commissioning, UPS discharge testing, and switchgear proving, across a capacity range of 30kW to 2500kW.Whether you need a portable resistive unit for a small standby genset or a containerised load bank for data-centre or utility-scale commissioning, we help you specify the right load type, capacity, and power factor for your test requirement.

What Is a Load Bank?

A load bank is a device that draws a controlled electrical load from a power source — a generator, UPS system, or battery bank — and dissipates that energy, typically as heat. It's used to:

Verify a generator performs at full rated load, not just at idle or partial load
Prevent wet-stacking in diesel engines that habitually run under-loaded
Test UPS and battery systems under realistic discharge conditions
Prove switchgear, transformers, and alternator excitation (AVR) response under load
Commission new power installations before they go live

Most acceptance tests don't use one load type alone — they combine resistive, reactive, and capacitive loading to reproduce the real power factor a generator will see in service.

Types of Load Banks We Supply

Resistive Load Bank — Unity Power Factor (PF 1.0)

Resistive load banks convert electrical energy directly into heat through fixed or stepped resistor elements, air- or water-cooled. This is the most common and straightforward load bank type, loading the generator and its prime mover equally at PF = 1.0.

Best for: genset commissioning, UPS and battery discharge testing, removing wet-stacking in diesel engines. Typical control: contactor-switched loading in 5–10% steps of rated kW.

RLC Load Bank — Combined Resistive, Inductive & Capacitive Loading

RLC load banks combine resistive (R), inductive (L), and capacitive (C) elements so a source can be loaded at a chosen lagging or leading power factor — typically down to 0.8 PF — reproducing the motor, transformer, and electronic loads a generator will actually carry.

Best for: full-load acceptance testing at rated power factor, transformer and switchgear proving. Typical control: independently switched resistive, inductive, and capacitive banks.

RCD Load Bank — Resistive-Capacitive for Diesel Genset Testing

RCD load banks pair resistive elements with a capacitor bank to create a leading power factor, used specifically to verify alternator AVR and excitation response under leading loads during diesel genset works testing. (Note: "RCD" isn't a fixed international designation — configurations vary by manufacturer, so we confirm exact specifications against your test requirement before quoting.)

Best for: factory works testing, AVR/excitation proving on diesel gensets. Typical control: resistive steps plus capacitor stages.

Load Bank Capacity Range — 30kW to 2500kW

We supply and specify load banks across the full range, matched to the scale of the test:

Capacity Typical Format Common Use

30–100 kW Portable / trailer-mountedSmall standby generators

100–500 kW Skid-mounted Commercial gensets, UPS testing

500–1200 kW Fixed or trailer bank Industrial and hospital gensets

1200–2500 kW Containerised bank Data-centre and utility-scale commissioning

Load Bank Specification Comparison

ParameterResistiveRLCRCD

Power factor1.0 (unity) 0.6–1.0, lag or leadLeading PF only

Load elements Resistor grids Resistors + reactors + capacitorsResistors + capacitors

CoolingForced air or water Forced air (oil-filled reactors on larger units)Forced air

Typical voltage 230V – 11kV400V – 11kV400V – 6.6kV

Common standards IEC 60947, NFPA 110IEC 60947, ISO 8528ISO 8528 (genset works test)

Best fitUPS/battery discharge, wet-stacking removalFull-load acceptance at rated PFAVR/excitation proving, leading-PF checks

Why Choose DKS Enterprises for Load Banks

Specification support across resistive, RLC, and RCD configurations
Capacity matching from 30kW portable units to 2500kW containerised systems
Guidance on power factor, cooling, and control requirements for your test standard (ISO 8528, IEC 60947, NFPA 110)
Engineering support drawn from our wider power and industrial parts supply experience

Frequently Asked Questions

What is the difference between a resistive and an RLC load bank? A resistive load bank only loads a generator at unity power factor (1.0), using resistor elements to convert power to heat. An RLC load bank adds inductive and capacitive elements so the load can be applied at a lagging or leading power factor, reproducing real-world loads like motors and transformers.

What load bank size do I need for my generator? Load bank capacity should generally match or slightly exceed your generator's rated output. For a 500kW generator, a 500–600kW load bank is typical, sized in steps that let you test at 25%, 50%, 75%, and 100% load.

Why is load bank testing necessary for diesel generators? Diesel generators that run habitually under-loaded develop wet-stacking, where unburned fuel accumulates in the exhaust system. Regular load bank testing at or near full rated load helps prevent this and confirms the generator will perform when it's actually needed.

Do you supply load banks for data centres? Yes — for larger installations we specify containerised load banks in the 1200kW–2500kW range, suited to data-centre and utility-scale generator commissioning.

Get a Load Bank Quote

Tell us your generator or UPS capacity, required power factor, and test standard, and we'll help you specify the right resistive, RLC, or RCD load bank for the job. Contact us