Power surges should I worry

[Tim Elett]

From time to time I noticed that the power surges not really so badly as a total brown out,but enough to be noticed, should I be concerned about it with a lathe with a variable speed control. We have a 100 amp service to gradge ,and 100 to house. I have noticed this in the house without running shop machines, they are just 110 volt, and mostly ran one at a time, other than the dust collection and saw or lathe

[roger wiegand]

Assuming that you are in the US, if your voltage is fluctuating outside the 114-124V window that is considered normal, and doing so at the service entrance (measure on the hot side of your main breaker, or call an electrician of you're not comfortable doing that) you should call your power company to check the lines. They will attach a load tester that will stress-test the system. One of the most common causes is a faulty neutral connection that the POCO can readily check for.

If voltage is steady at the service entrance but varying inside your house/shop, then you probably need to call an electrician. Again, bad connections on the neutral are a common cause.

Sometimes attaching a recording voltmeter is useful to see how much variation there is over a day or two. Either your electrician or the POCO should be able to do that. They are expensive enough that you probably don't want to buy one.

[Jim Becker]

The two machines in my shop that never remain plugged in when not in use are my Stubby lathe and my CNC machine...for exactly the reason you mention. I want them isolated from any potential surges and neither have a real disconnect in them natively. While my machines are 240v, it really doesn't matter...a surge is a surge and electronics can be damaged regardless if they are 240v or 120v..

[Bruce Volden]

I live in the "country" where sags and spikes happen frequently with incoming power transmission lines.
I also have a laser engraving business with computers......
When I'm running the laser it is plugged into an APC voltage regulator which is 'sposed to stabilize and condition line voltage.
It must work because the laser is over 20 yrs. old!!
ALL my computers utilize a battery backup/line conditioner as well.

Bruce

[Bill Dufour]

Square D, and I assume others, make a whole house surge protector that simply plugs into the breaker panel. It uses two spaces like any other 240 V breaker. It does have a neutral wire that has to be screwed to the neutral bar. It may have a clip on neutral as well. Sold on ebay for around $50.
Recomendation is to install them in the position closest to the infeed from the pole. For my refrigerator I installed a surge protector outlet since there was no room for a power bar.
Bill D.

[Tim Elett]

Thanks to all ,so I'm thinking that I should have a surge protection on the lathe power,every thing else is just motors.

[Lee Schierer]

I just installed a whole house surge protector. It took less than 15 minutes. I ordered it from Amazon.

[Ken Fitzgerald]

I travel a bit and I unplug all the tools in my shop before I leave for extended periods. My computer is on a surge protector but I remove power from the computer when out of town on extended trips. Professionally I have dealt with the effects of power surges on equipment used in radiology departments. I even had the dubious pleasure of repairing an approach radar used in air traffic control following a lightning strike hitting the ground and running into the unit via the power lines. That repair took a couple weeks!

[Tim Elett]

I remember at our place we had , in Michigan, lightning hit a tree,and I followed the raised ground along the power line to the house. The cable box was tosted.i will look into a Serge protection. Thanks

[Bill Dufour]

A line reactor or load reactor will help reduce surges. A used three phase one will do fine on single phase. Motor loads, including home vacumms are the major internal surge sources.
Bill D

[Alan Lightstone]

In my previous house we had a lightning strike that destroyed $55K worth of electrical equipment. Entire home theater, HVAC units, every light switch in the house. It probably entered the house via the cable, then travelled through the house over low voltage cabling, not the AC wiring. The home theater was actually destroyed even though not plugged in (but network cabling was). So I'm a big fan of whole house surge protection.

On another issue, that house had daily brief interruptions of power (~1 sec). The utility denied anything was wrong, so I called and called until they place a monitoring device on the house (recording volt meter), They kept it on the mains for a month. In that time we had multiple brief power outages. When they took it off, they said everything was perfect and no power outages. So you have to rely on the utility to be truthful. In my encounters, I have found them to all be slime. YMMV.

[Robert Engel]

Thanks to all ,so I'm thinking that I should have a surge protection on the lathe power,every thing else is just motors.

I asked my electrician about this, his answer was "you won't know if it works until you get a strike."

[Charles Lent]

A bad Neutral to ground connection in the house mains can cause all kinds of strange problems. Lights that go bright sometimes and flicker others is a good indication of a neutral to ground connection problem. If your electric service has main fuses and they are 10 years old or older, they can become high in resistance and produce similar results. They aren't that expensive, so just buy new and install them.

I have fixed many of these in my years as a licensed electrician/EE. It is sometimes a power company problem, but much more often poorly maintained electrical service equipment and neutral connections to ground.

Charley

[Bruce Lowekamp]

This conversation seems to be mixing brownouts, surges, and lightning strikes.

You should make sure your house is grounded properly (proper ground in the panel, routed to grounding rod outside and water system tied in)

You can’t really do anything about brownouts. (well, you can use a UPS for computers, but that doesn’t help with a lathe.)

For surges, I think everyone should have a whole-house surge supressor. I don’t bother beyond that (have a whole-house surge suppressor and then UPSes on computers etc). Might be worth a secondary surge suppresor if you have valuable electronics that aren’t on a UPS.

For lightning strikes, proper grounding is your first line of defense. Beyond that a lightning suppresions system (lightning rods) would help but quite expensive. You need to prevent the lightning strike because you can’t absorb it if it hits your house or lines nearby.

Bruce

[Charles Lent]

The present National Electric Code requires two 8' copper clad ground rods to be installed, spaced at least 5' apart and connected to the main electric panel ground buss, with the neutral buss then connected to the ground buss at this one location. My property is at the end of a road and the last service point on that road for the power company. I also have lakefront property, so the water table in the ground is less than 20' below the surface. When I bought the property there was evidence of power problems with poor grounds and the panels were old and fused. I replaced the meter hub and the main and sub panels with modern breaker panels and assured that I had everything grounded very well and above the code requirement. My home now has those two required copper clad 8' ground rods, plus a third 8' copper clad ground rod buried horizontally 3' deep near the main electric panel. A fourth 8' copper clad ground rod is located just outside my shop and connected to the ground buss of the sub panel within my shop. My shop is located 200' from my main house panel. A fifth 8' copper clad ground rod is located 4' from my well that is 150' from the house. It is connected to the ground buss in the well house sub panel, so 5 ground rods are on my house electric service and the service cable to my house and to the sub panels in the shop and well house are all 4-5' underground. If you have metal water pipes in your home, they need to be ground connected to your electrical ground system. Also assure that your telephone and TV Cable service points are connected to this grounding system, even if the phone and cable services insist on adding their own ground rods. Just jumper connect every one of their grounds to your ground system, above the ground and in plain sight, so you can inspect these jumpers often, as most of their installers don't understand proper grounding and may attempt to remove them. When a lightning strike occurs you want all of the wiring entering your home to be grounded and held at the same voltage level. My main service panel also has a power company installed surge/lightning supressor in it. Other than some occasional small and very short voltage dips from neighbor AC systems starting, I don't have any power problems, and no concerns for power line lightning strikes either. All of this has been in place for almost 40 years, so if the system was inadequate in some way, it would have shown by now.

Grounding of your power system is highly important. If you have less than 2 ground rods on your electric power service you should add at least one other at the minimum. You will likely be very surprised at how much more stable your electric service becomes. I'm a licensed electrical contractor and EE (now retired and a full believer in good electric service grounding. I have solved many electric service problems in my career.

Charley