It takes routine maintenance and knowledgeable engineers to keep an electrical system running smoothly. However, there are a couple of problems that can be hard to catch, even to a skilled eye. And left untreated, they can shut down your system and run up a pretty hefty bill for downtime and repairs. Here are some of the worst problems your electrical system will face.
Harmonic Distortion
Harmonic distortion is defined as any changes within current frequency 
cycles. This phenomenon is the culmination of unwanted high frequency AC voltages or currents supplying motor windings with energy. This additional energy circulates in the windings, eventually causing there to be internal energy losses. The losses dissipate in the form of heat, deteriorating the insulation and capability of windings and causing issues within motors, transformers, circuit breakers, fuses and relays. Eventually, the motor efficiency is weakened, causing more money to be spent in repairs and an increase in system temperature beyond optimum levels. Can be diagnosed with Power Quality Analyzers and Oscilloscopes.
Product: Tektronix TD S684C Real-Time Oscilloscope
Voltage Imbalance
Three-phase electrical distribution systems often service single-phase loads. When a significant difference in phase voltages occurs – typically characterized by a difference of more than 2% - motors and transformers begin to overheat, causing imbalance across all phases. This is referred to as voltage imbalance, and it can cause excessive current flow, increased operating temperatures, and eventual insulation breakdown. Voltage imbalance generally occurs in the motor cabling, terminations, or even the windings. Can be diagnosed with Power Quality Analyzers.
Product: Yokogawa WT3000 Power Quality Analyzer
Voltage Dips and Swells
Voltage dips and swells are generally the result of very large loads either starting up, or shutting down from an overload. A voltage dip can be described as the outcome of a motor's rms voltage rapidly decreasing between 10 and 90% of its average voltage. This can impact and eventually damage electronic controls, devices like computers, or even lamps. Power Quality Analyzers can be used.
Product: Vibralign Fixturlaser EVO Laser Shaft Alignment Tool
Flicker
Flicker is visibly seen as change in brightness or a rapid switch from on to off in lights and lamps. The fluctuation in light sources is caused by cyclic voltage dips within the power supply. Though flicker is mostly detrimental to employee productivity alone and doesn’t pose a huge threat to equipment, it can cause an epileptic attack on those with photosensitivity. Flicker must then be measured by IEC 61000-4-15, which requires an assortment of equipment.
Product: Commtest VB7 Dual Channel Vibration Analyzer
Transients
Transients are defined as brief, sharp voltage spikes. These voltages can be the result of a number of factors – loads turning on/off, tan delta correction capacitor banks, or even weather. Each of these are capable of causing damage, from erosion of insulation to breakdown in motor windings. If you have locked-up computers or burnt out circuit boards, you likely are dealing with transients. Left untreated, voltage transients will cause breakdowns that lead to early motor failure and costly downtime. Can be diagnosed with Power Quality Analyzers.
Product: Flir T420 Infrared Thermal Imaging Camera
The above issues will rear their head in different ways. The source of your electrical trouble may not always be clear. That said, if you notice any of the below symptoms of a growing electrical problem, it’s time to stop and take a look at the health of your system.
- Continual, frequent equipment failures
- Overheating motors or transformers
- Intermittent and random equipment resets, process failures
- Breakers that trip, fuses that blow – with no warning signs of overloading
- Uninterruptible power supplies going on line
Testing for these issues can be done with a variety of electrical diagnostic and maintenance equipment.
Power Quality Analyzers,
Oscilloscopes,
Infrared/Thermal Cameras,
Vibration Testers, and
Laser Shaft Alignment Tools are all equipment that can be used. For more information on how protect your facility from devastating equipment failure, please feel free to contact our electrical team leads.
Posted June 21, 2017