What do beer and power fuses have in common?
Before we start talking about beer or capacitor fuses we’ll set the stage by briefly describing what a capacitor is and what it does.
Capacitors Stabilize Electrical Systems
A capacitor is a passive two-terminal electrical component that stores electrical energy. Capacitors are commonly used in power transmission systems to stabilize voltage and power flow. Capacitors are also used in power conditioning applications where they are connected in parallel with power circuits to shunt (pull) away current fluctuations from the primary power source to provide a “clean” power supply. See “Gold Rush” article for more on fusing for Power Distribution quality.
In electric power distribution, capacitors are used for power factor correction. The power factor of an AC electrical power system is defined as the ratio of real power flowing to the load to the apparent power in the circuit.
Brewing Power Factor Ingredients
In other words, power factor is a measure of an electrical system’s efficiency. kW is the real power which powers the equipment. kVAR is the reactive power that magnetic equipment needs to produce magnetizing flux. kVA is apparent power which is the product of the current and voltage of the circuit.
When energy is stored in the load and returned to the source or a non-linear load distorts the wave shape of the current drawn from the source the apparent power will be greater than the real power. Power Factor correction capacitors are capable of aligning the ratio to 1 thereby improving the capacity and voltage of electrical systems to reduce power loss.
[pullquote align=”full” cite=”” link=”” color=”” class=”” size=””]What does beer have to do with all this? … Foam = Reduced Power![/pullquote]
Capacitors and the Beverage Equation
Want to know more about what electrical power efficiency has to do with Beer? This analogy from the Electrical Energy Portal may help you understand Power Factor.

What do Beer and the Power Factor have in common? (source: Electrical Engineering Portal)
Capacitor Fuses for Capacitors
A Capacitor Fuse provides both short circuit and overload protection of the Capacitor. The primary responsibility of capacitor fuses is to isolate a shorted capacitor before it can damage equipment or injure workers. Most capacitor failure occurs when the dielectric (electrical insulator) in the capacitor cannot withstand the applied voltage. The excessive heat generated builds pressure that can cause violent case rupture. The capacitor fuse will isolate the shorted capacitor before rupture occurs.
[pullquote align=”full” cite=”” link=”” color=”” class=”” size=””] It’s the principle behind the quality of your facility’s power consumption and your favorite carbonated beverage[/pullquote]
Eaton Cooper Power NXC Capacitor Fuses

Capacitor fuses (Top) offering power system protection to capacitors.
Consider the EATON Cooper Power Systems NXC Full Range Current-Limiting Capacitor Fuse. The Eaton NXC capacitor fuse allows fusing of at least 50,000 joules of parallel connected energy providing greater application latitude in the various capacitor bank designs available.
The Cooper NXC Capacitor Fuse has a positive leader wire ejection for reliable interruption and capacitor isolation eliminating stress to remaining apparatus. Top end cap includes provision for bus bar mounting. Design also includes visible indication of a sensed fault and there are no mechanical operations for clearing or indicating functions.
The NXC Fuse performs effectively under both high and low fault currents due to its fast full-range clearing capacity.
NXC Capacitor Fuse Applications
- high fault areas
- fusing of individual capacitors
- capacitive circuits that need positive isolation
- circuits requiring let-through current restriction
- areas where burning debris is problematic
- areas where high noise levels are undesirable
Capacitor Fuse Placement
Fusing each individual capacitor is extremely important in large banks of parallel capacitors. Without an overcurrent device, if one capacitor should fail, the parallel capacitors will discharge into the faulted capacitor and violent rupture of the faulted capacitor can result.
Capacitor Fuse Sizing
Power transmission and distribution systems come in all sizes and configurations and handle a wide range of currents. You can avoid fuse sizing mistakes when selecting and correctly sizing replacement fuses for power distribution systems. Proper fuse selection depends on many factors, so consult a professional engineer for your application.
NXC Current-Limiting Capacitor Fuse
Available from Monster Fuses in 8.3, 15.5 and 23kV.
Factory Authorized Provider of All EATON Fuse Products
Eaton Cooper Power Systems NXC Fusing Catalog Numbers
FA5J10, FA5J18, FA5J25, FA5J30, FA5J40, FA5J45, FA5J65, FA6J10, FA6J12, FA6J18, FA6J25, FA6J30, FA6J35, FA6J43, FA7J12, FA7J18, FA7J25

EATON Cooper Power Systems – NXC Capacitor Fuses
Can Beer Give You More Power?
Not really, but to understand why your facility’s power bill is so high, it may help to remember that Power Factor is the principle behind the quality of your facility’s power consumption and your favorite carbonated beverage.
Monster Fuses is a Factory Authorized
Provider of All Major Fuse Lines.
Stocking Capacitor Fuses from EATON Cooper Power Systems, EATON Cooper Bussmann, S&C, Mersen/GE, ABB, SIBA and more…
Monster Electrical is a “knowledge-based” independent distributor of fuses, fuse hardware and control equipment. We don’t just ship boxes. Our product and application knowledge goes into every transaction.
Monster Fuses provides immediate shipment of power fuses and power fuse mountings from our extensive inventory. Clients can access more than 14,000 power fuse solutions provided from a stock of 100,000+ fuses, eliminate long factory power fuse lead times, and supply real time solutions for urgent fuse challenges in utility, industrial, institutional and commercial applications.
Monster Controls provides immediate shipment of 5kV Class control components. Clients can access thousands of 5kV class control parts from an extensive inventory, eliminate long factory lead times and supply real time solutions for electrical control challenges. Specializing in parts for 2.3kV, 5.5kV and 7.2kV motor starters, contactors and switches, Monster Controls also stocks complete starters, contactors and switches.
Need help calculating fuse current ratings for transformers or selecting fuse hardware, power equipment and electrical replacement parts? Call 888-444-4335 in the West or 877-444-1798 in the EAST.

Contributing Author Greg Carter has been working exclusively in Industrial/Electrical Digital Marketing and e-commerce for over 15 years.
Company website: electricalmarketing.net.
email: gcarter@electricalmarketing.net. | Direct 856.381.7834.