# What's the difference between a surge and a spike in voltage?

Posted by on

### Charles

• Level 1:

An expert who has achieved level 1.

New Friend:

An expert that has 1 follower.

• Contributor

1. Steady-State Voltage - Steady-state rms voltage values are those that stay constant for 10 seconds or longer. 2. Nominal or Normal Voltage - The normal planned voltage for a system. For most equipment this is 110-125VAC.
3. Power Failure - A power failure is a zero voltage condition lasting for more than one cycle (1/60 second) on any one of the three phases being used.
4. Blackout - A total power failure lasting several seconds to hours or more.
5. Brownout - A planned and generally announced city or regional-wide reduction by the utility in the steady-state voltage possible due to heavy electrical consumption.
6. Undervoltage - A continuous reduction in the steady-state voltage below the normal voltage. Similar to brownout but this term is generally used to refer to unplanned reductions or localized problems within the building or circuit.
7. Overvoltage - A continuous exceeding of the normal voltage.
8. Sag - Sags are cycle-to-cycle decreases in the power line voltage on any one of the three phases below the normal value. The lasting time of a sag is its duration in the number of cycles of the 60HZ line frequency that the disturbance is below, and returns to the normal level.
9. Dip - Dips are very short (but visible in incandescent light bulbs) decreases in the normal power line voltage. These are similar to sags but are noticeably faster. A dip is a fast sag.
10. Surge - Surges are cycle-to-cycle increases in the power line rms voltage on any of the three phases above the normal voltage. Lasting time for surges is measured the same way as are sags.
11. Swell - Swells are longer term multi-cycle slow rising surges lasting from a few seconds to several minutes.
12. Impulse - An impulse is a very short term disturbance up or down superimposed on the AC sine wave that typically lasts between 0.5 and 100 microseconds. In-phase going impulses which increase the instantaneous voltage are called spikes. Out-of-phase impulses which decrease the instantaneous voltage are called notches.
13. Spike - An over voltage impulse ranging from 400V to 5600V or more which is superimposed on top of the AC sine wave. These, when over 600V, are potentially very damaging disturbances.
14. Notch - An under voltage impulse similar to a spike but of reverse polarity to the instantaneous value of the AC sine wave so as to take a momentary notch out of the sine wave. Notches are typically too fast to see. These typically last as long as spikes but can be up to several milliseconds. In addition, spikes and notches usually come in pairs or in an oscillating series. For every notch there is usually an immediately following spike due to power line inductances and capacitances.
15. Transient - A transient is any short-term non-normal event on the power line. All power line disturbances are transient by definition.
16. EMI - Broad spectrum electromagnetic noise interference either conducted on the power line directly from the source or radiated to the power line then conducted to the susceptible equipment.
17. RFI - Electromagnetic noise interference in the radio spectrum.
18. TVI - Electromagnetic noise interference in the television spectrum.
19. EMP - A very large and very fast rising electromagnetic pulse caused by catastrophic events such as lightning or nuclear detonation.
20. Harmonic - Harmonics are sinusoidal currents and voltages with frequencies that are integral multiples of the fundamental power line frequency. Harmonics distort the normal sine wave.
21. Normal Or Differential Mode - Events which occur across the normal current carrying wires of the power line-hot wire to neutral wire. Also called the transverse or metallic mode.
22. Common Mode - Events which occur from the current carrying wires, hot and neutral, relative to the safety wire-ground.
23. MOV - Metal Oxide Varistor. A voltage dependent resistor. A low cost but very effective protection device. They can handle large surges and switch in 1 to 5 nanoseconds. It works by absorbing voltage surges and spike impulses. They are most effective when used in groups of three to provide both differential mode and common mode protection.
24. Silicon Avalanche Zener Diodes - A solid-state junction device. These devices are very fast acting but have low energy handling capability. Switching speed is in picoseconds. They work by shunting the surge or spike impulse around the protected circuit.
25. Gas Discharge Tube - A calibrated spark gap in a gas filled chamber. These devices are relatively slow, activating in microseconds but can handle very large surges. They work by shunting the surge or spike impulse around the protected circuit.
26. EMI/RFI Filter - A circuit or device containing series inductive (load-bearing) and parallel capacitive (nonload-bearing) components which provides a low impedance path around the protected circuit for high frequency noise. Filters also attenuate impulses since a Fourier's Analysis of a spike will reveal it is composed of high- frequency waveforms. Filters and surge suppressors when used together thus act synergistically.
27. UPS - An Uninterruptible Power System which provides a steady source of electric energy to a piece of equipment.
28. Continuous UPS - A UPS system for which the load is continually drawing power through the batteries and inverter and never directly from the normal AC power line.
29. Standby UPS - A UPS system which normally connects your equipment to the normal AC power line with the batteries and inverter in standby mode. When the power line is weak or fails it transfers the load to the batteries and inverter without any load malfunction and without any user action. When the power line returns to normal the load is automatically retransferred back to the AC power line.
30. Voltage Surge Suppressor - A fast acting circuit or device containing MOVs, Silicon Avalanche Diodes, Gas Discharge Tubes, or other components which suppresses voltage surges and spikes to a safe level. The energy in the surge or spike is either dissipated as heat in the protection components or is diverted to earth ground by the circuitry.
31. Voltage Regulating Transformer - A continuous acting transformer, usually ferro-resonant, which instantaneously regulates the output voltage to normal levels despite wide swings in the input voltage.
32. Voltage Stabilizer - A switching device which selects appropriate windings of a transformer to maintain normal output voltage levels despite wide swings in the input voltage. Switching occurs after the power is non-normal for a few seconds. This device is commonly confused with a voltage regulating transformer but they differ greatly in response time. Stabilizers are generally too slow to protect solid-state devices.
33. Power Line Conditioner - A PLC is a combination of a voltage regulating transformer with a super isolation transformer which provides smooth, regulated, noise free, AC voltage with no ohmic connection between input and output. A PLC will solve most problems other than complete power failure.

Posted on Nov 11, 2014

### Rachel

• Level 2:

An expert who has achieved level 2 by getting 100 points

New Friend:

An expert that has 1 follower.

Hot-Shot:

An expert who has answered 20 questions.

Corporal:

An expert that hasĀ over 10 points.

• Expert

A spike is an increase in voltage for 1-2 nanoseconds.
A surge is the increase lasts 3+ nanoseconds.

Posted on Feb 05, 2014

×

my-video-file.mp4

×

## Related Questions:

### What can you use to protect your computer from voltage spikes

a surge protector or a backup battery with surge control or a whole house surge protector. Google it very same question google search.

Jul 22, 2017 | Computers & Internet

### Model 253.28432807. Household power went off today for a couple of hours. Restored. Freezer has power but display is illegible. Up arrow does nothing. Down arrow changes display but display is erratic and...

Electronic components are very sensitive to voltage surges, spikes or sags.

Voltage is not delivered at a constant 120 volts. With alternating current, the voltage rises and falls in a predetermined rhythm. The voltage oscillates from 0 to a peak voltage of 169 volts. Most appliances and electronics used in the United States are designed to be powered by this form of generated electricity.
During a power surge, the voltage exceeds the peak voltage of 169 volts.

A spike in voltage can be harmful to appliances and electrical devices in your home. An increase in voltage above an appliance's normal operating voltage can cause an arc of electrical current within the appliance. The heat generated in the arc causes damage to the electronic circuit boards and other electrical components.

(Smaller, repeated power surges may slowly damage your electronic equipment, over time too.)

Voltage sags, a.k.a voltage dips or brownouts, is another form of electrical disturbance that can damage appliances as well.

The bottom line, power surges, spikes, and sags can vary in duration and magnitude; and can damage electrical equipment ranging from stereos to computers to any household appliance that uses chip board circuitry sensitive enough to "blow" due to over or under-energizing it.

Jul 03, 2014 | Kenmore Freezer 20.3 cu. ft. Frost Free...

### Can anyone advise what might be wrong with my Acer Aspire L100. We had a power cut the other night and it knocked off her computer. The unit will not restart and is completely dead. Are there any simple...

I am assuming you weren't plugged into a surge protector when you lost power. During power outages, spikes in voltage occur, so what happens is there's no mechanism to interrupt that spike by grounding, which surge protectors are designed to do. Any laptop/computer components cannot handle this voltage spike as they are delicate to certain voltage tolerances. I hate to say it, but your laptop is toast.

Jul 28, 2017 | Acer Aspire L100 PC Desktop

### Damage to equipment from power surge

yes a spike may destroyed the mov (metal oxide variastor) inside projector replace it problem will be solved spike comes in the case of storm and lightning strike apc ups are well protected from spike and surge

Mar 04, 2010 | APC Back-UPS XS900 (BX900) UPS System

### Hi we have problem with 6kva 9120 eaton ups,

Maybe you have many overvoltage situations at your area, that the UPS can't handle. It's a good idea to put before the ups an overvoltage protection or a stabilizer. Ask the manufacture for the overvoltage protection of the ups that can handle.

Stelios.

Feb 22, 2010 | Eaton PowerwareĀ® 9120 UPS System

### Donno how to use

Hi,

Surge protector, minimizes voltage spikes or burst that could damage your electronics. You may not see it doing anything but it does. It clips those voltages to the right rating befrore letting them in to your system.

I hope this helps.

Jun 14, 2009 | APC BE325 SURGE PROTECTOR + BATTERY...

### HP6150 - won't turn on after the last thunderstorm. It's not a circuit breaker or GFCI problem. Power cord has a green light, which is on.

Lightening does hit power lines, and cause voltage spikes; these voltage spikes do burn out electronic equipment. Surge protectors are used to prevent these voltage spikes from burning out electronics

Jun 11, 2009 | HP Photosmart C6100 All-In-One Printer

### Surge protectors

Before anything else, it's probably best to explain the differences between power surges and flux. Power surges (also called voltage or electrical spikes) are generally caused by a sudden, massive increase or decrease in the voltage flowing through an electrical circuit. Flux, on the other hand, can be defined as the actual voltage flowing through a circuit at any given time.

Whenever an electrical device turns on, turns off, or changes modes of operation, it can cause slight disturbances or differences in the voltage flowing through an electrical circuit. Exactly how much of a difference is made may be dependent on the type of electronic device attached, though major electronics and appliances will have a larger "pull" than smaller devices, like clock radios. The more devices are attached to the same circuit, the larger these voltage differences may become.

This fluctuation in voltage - combined with other electrical, magnetic or radio frequency interference ("noise") - has been known to cause problems or even damage in some electrical devices. To prevent such damage, many manufacturers may include "noise reduction" or "EMI/RFI protection" features in their surge protectors.

As both Dynex and Monster Cables appear to include such a feature in many of their products, the price difference you are seeing may simply be related to the number of additional features that the Monster Cable surge protector offers, though this cannot be guaranteed.

If you're in doubt about your purchase, I would strongly suggest contacting either manufacturer for more information. Most manufacturers are able to provide you with detailed descriptions of their product features, and one of the two may be able to point you towards an online FAQ if one is available. Dynex's toll-free hotline is 888-305-2204, and Monster Cable can be reached at 415-840-2000.

Hope this helps you out.

Sincerely,
Aaron

Jul 18, 2008 | Televison & Video

### Surge Protector

Surge Protectors are devices that usually you plug your equipment to.. and it protects it from Voltage Spikes that would otherwise destroy the device without it.. saddly not all Surge Protectors are the sam.. some are completely useless..

If you are really serious about protecting your PC not just the hardware but also the data and your work.. might as well invest on a UPS(Uninterrupted Power Supply) unit.. it has everything a surge protector can offer and more..

Apr 28, 2008 | MSI 845E Max2 LR Motherboard

### Voltage Spike / Power Surge Harman Kardon AVR 130

In this case is pretty hard to give a diagnostic. There are plenty of possibilities. It has to be seen by a tech

Apr 05, 2008 | Harman Kardon AVR 130 Receiver

#### Related Topics:

671 people viewed this question

Level 3 Expert

Level 3 Expert