Nova DVR and surge suppressor

[Keith E Byrd]

I saw several references to the Nova DVR and the need to use a surge suppressor. I am finishing my bench tonight and plan to set up my Nova tomorrow night so my question is:
Is there a special surge suppressor that I should use? Are you referring to one's like the power strips you use to plug computers into? I don't want to take any chances and end up blowing the electronics.

[Steve Vaughan]

Keith, I had the same questions when I got mine a couple years ago. For the first year, I had the circuit that it was plugged into that was protected with one of those ground fault circuit protectors and then a surge protector at the lathe itself. But, then, last year I switched it over to 220v and have it plugged directly into the receptacle with no protection. That kind of concerns me. I keep the unit turned off whenever it is not in use just to avoid issues.
I be curious about other responses cause I'd kind of like to figure out how to protect it on the 220 line.

[Ron McKinley]

Do a search on 220 volt surge protectors and you'll find plenty out there at electrical specialty houses.......Ron

[Bob Borzelleri]

The irony of the surge suppressor thing is that most people who use them have several in various locations around the house/shop, etc. If you add up the cost of several good surge suppressors, you very quickly approach or pass up the cost of a quality whole house surge suppressor for the main panel.

[Clint Baxter]

I used a surge arresting double pole breaker to supply the electrical feed to my DVR. It also provides surge suppression for the entire panel. Ran about $100 from my local electrical supply house. I had issues when I was connected 120V circuit before but have had no issues since.

Good luck.

Cllint

[Scott Crumpton]

The irony of the surge suppressor thing is that most people who use them have several in various locations around the house/shop, etc. If you add up the cost of several good surge suppressors, you very quickly approach or pass up the cost of a quality whole house surge suppressor for the main panel.

Economics and engineering are often at odds with each other. True, one whole house suppressor is less expensive that many individual units. But lightning doesn't understand economics, it follows the laws of physics with actions best explained by RF field theory. A strike can induce voltages in house wiring at any point, totally independent of any particular surge suppressor. The closer the suppressor is to the device, the more likely it is to protect that device. A whole house suppressor can try to protect the entrance point from spikes passing through that point and little more.

More important than any surge suppressors is a unified ground system for all devices. For example, imagine a computer, printer, monitor, and maybe one or two other AC powered devices. They're all connected together by data lines of one form or another. If you plug them into different wall outlets they are much more likely to suffer lightning damage than if plugged into a single power strip. This is because different voltages can be induced in the independent grounds. This can cause ground loop currents in the data cables between the devices and subsequent damage to one or more of the devices. The optimal configuration for a computer system is: outlet --> surge suppressor --> coiled cord to UPS --> UPS --> short cord power strip if necessary --> all the devices. Ideally, no copper should be connected to the system that does not use the UPS as the ground point. Also, the "coiled cord" is actually important. It creates an inductor that will slow the pulse that get's past the first surge suppressor, maybe allowing the UPS just enough time to act and save the rest of the system components.

The point I'm trying to make is that lightning is very powerful and even more unpredictable. As much as a kink in a ground wire can cause the current to flow into the device rather than to ground. Yes, just a simple kink can create enough of an impedance bump to render a ground wire ineffective. Where I work we have large copper buss bars around the perimeter of entire rooms with all equipment racks connected to it with large cables.

My best advice for 120v devices like your TV/VCR/DVD/Stereo center put a good surge suppressor at the outlet, plug in a good surge suppressing power strip, coil the cord, and plug everything into that one power strip. For devices that don't need to be plugged in all the time like your lathe, use an appropriate surge suppressor for when you forget to unplug it. Unplug it when not in use, particularly if the inverter remains powered up as it does on the Powermatics.

Surge suppressors (good ones that cover all three legs) are cheap insurance. Unplugging is free insurance.

---Scott.

[Ralph Lindberg]

Scott offers really good advice. Also, consider propagation time and location of the surge. If the surge "comes in" the main, a main panel one really works well. But if a motor burns up and causes a back EMF.... A friend lost his computer when the electric mower died, badly one day.

I haven't lost any electronics in years. Here is what I have
A main-panel surge.
The TVs, Computers, Ham Radio gear and SWMBO's fancy electronic sewing machines are all plugged into GOOD (not CHEAP) surge-emi-rfi strips. As is the DVR-XP.
Before I went to this system I was losing one piece of "something" every winter (we are rural, with bad storms and when the power goes out/comes back, bad things happen)

TTFN
Ralph (BS-EE, Amateur Extra, Geek, ie I play with a lot of electrons)