Surge Suppression

[Ted383]

I want to protect my plasma/router table electrics, torch height control unit and PC with a surge protector. According to the manufacturer the motion control box draws 20 amps and has a 20 amp breaker inside. It runs 4 stepper motors (I don't know the size) and Gecko drives.

Every suppressor I've seen is rated at 15 amps. I talked to a guy at Monster Cable and he said not to use one of their 15 amp models.

The plasma table manufacturer says he runs all of his machines on a typical 15 amp suppressor.

Am I doing the math wrong here?

[Al_The_Man]

Maybe what you should be looking at is what needs protection from what?
What is putting out interference and what will suffer from it the most?
IOW, I would use inline suppression on the PC and the height controller.
Manufacturers like Corcom have R/L/C type inline filters
Things like Plasma controllers put out interference, they do not usually need protection from it!.
Plasma controllers and Servo/steppers drive supplies, usually have very low impedance power supplies, that although capable of absorbing alot of energy, they may radiate some into more sensitive sections of the system.
Al.

[Ted383]

I am mainly looking to protect the mentioned components from power surges. I would also like to "condition" the power going to them. Most quality surge suppressor have them built it.

I had not considered interference problems. The machine manufacturer recommends a 30" space between the motion control box and PC, other than that all I have done is install 8' ground rod to both machine frame and plasma cutter.

I need to know if a standard 15 amp surge protector will work with the 3 components. -ted

[Al_The_Man]

What side of the power supply to the steppers is the breaker on, if you have just a 20amp breaker for the stepper primary supply, you are going to need a 25~30 amp supply.
If this is secondary current, your primary should be much lower.
The R/L/C type offer interference suppression and to a degree will suppress spikes and surges.
Corcom, (now Tyco) can supply 30amp types.
http://www.cor.com/Series/PowerLine/EMC/
If you want a regulated AC in, then you really need the Sola Basic constant voltage units, they are pricey and also are a bit of an energy waster as they run in saturation and run very hot.
Al.

[jimcolt]

I have used a low cost UPS (Uninteruptible Power Supply) available from office supply stores for over 6 years for the power for my PlasmaCam and for the PC. the unit has built in surge suppresion, lightning protection as well as battery backup. I lookeat at the wattage on the PlasmaCam and the PC.....added them together and doubled that.....that is the size I use. I think I paid $39 for the unit at staples.

Occasionaly I used to have either the PC or the PlasmaCam fault while I was cutting, usually when my compressor kicked on. The UPS elimitated that issue.

Jim Colt

[Ted383]

When I was looking into the things I'd need to learn to get my new plasma table set up, I expected certain things to be complicated...finding a surge protector/UPS was not one of them

My original plan was to buy a UPS. So I did. A got a Cyberpower from Best Buy, I think it was 425VA. When I moved the steppers the UPS alarm sounded and shut it down. I know a larger UPS would fix the problem but several people have told me (including PlasmaRoute) that the only way to guarantee component safety is to unplug them when not in use. But when you do that the UPS kicks in. I don't know if it's cool to do that every night.

There are formulas to calculate the size UPS needed for a given application but being that my PlasmaRoute motion control box is "homemade" it does not have a label. All I know is it draws 20 amps.

So then I figured just go with a good surge protector but that has it's complications too (see first post).

Jim, What size is your UPS?


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[westom]

Originally Posted by Ted383 I want to protect my plasma/router table electrics, torch height control unit and PC with a surge protector. ... Every suppressor I've seen is rated at 15 amps. I talked to a guy at Monster Cable and he said not to use one of their 15 amp models. ... Am I doing the math wrong here?

You are seeking protection from devices that do not even claim to provide hardware protection. Have doubts? View its manufacture numeric specs.

What does a surge seek? Earth ground. What is a perfect surge current path? Incoming on AC mains, through your table electrics, then to earth via a very good conductor - concrete floor. What would the Monster Cable do? Give that surge even more paths destructively through electronics.

From the NIST (US government research agency):
> You cannot really suppress a surge altogether, nor "arrest" it. What
> these protective devices do is neither suppress nor arrest a surge,
> but simply divert it to ground, where it can do no harm.

What must the Monster Cable products do? Suppress, arrest, block, or absorb that surge. Will not happen.

How does your telco, connected to overhead wires all over town, protect their electronics? Telcos spend no money on ineffective protectors such as Monster, APC, Belkin, Tripplite, etc. They need effective protectors. That means a 'whole house' protector located where every wire enters the building.

Either you earth (divert, connect, shunt, bond, clamp) that energy to earth BEFORE it enters a building. Or that energy hunts for earth destructively via household electronics. Telcos suffer about 100 surges with every thunderstorm - and no damage. Telcos locate every protector as close to single point earth ground as practical. In your case, that connection from each AC mains wire to earth ground must be less than 10 feet.

A protector is not protection. Popular myths promoted in retail say otherwise. Less responsible companies were listed above. Only the more responsible companies sell effective solutions: Siemens, General Electric, Intermatic, Square D, Leviton, Keison, Polyphaser, Cutler-Hammer, and Clipsal are but a few. But again, no protector provides protection - as the NIST noted. Protection is provided by what harmlessly dissipates that energy - earth. A protector is only as effective as its earth ground.

Did Monster Cable forget to mention that? Less responsible companies sell protectors for $25 or $150 per protected appliance. Profit centers; not protection. One 'whole house' protector is about $1 per appliance - tens of times less money. Actually protects the from typically destructive surge.

Essential to any surge protector is that dedicated and short connection to earth. All incoming utility wires (telephone, cable, satellite dish, etc) must all make a short connection to that same earthing electrode. Again, energy permitted inside the building will hunt for earth ground. A cable surge may eventually find earth destructively via your routing table.

Above is only secondary protection. Also inspect your primary surge protection system:
http://www.tvtower.com/fpl.html

How effective is a 'whole house' solution? The effective protector will even earth direct lightning strikes (to incoming wires or wires down the street) and remain functional. When promoting ineffective protectors, undersizing to periodically fail gets the most naive to say, "My protector sacrificed itself to save my computer." Effective protection means you never even knew the surge existed. Even the protector remains functional. IOW buy a protector from more responsible companies. Do not even consider Monster Cable - a company that routinely sells in markets ripe for scams.

Did you know speaker wire has polarity? Monster Cable speaker wire does? The naive will spend $70 for fancy Monster Cable wire because the polarity is marked on the cables. Which end must connect to speakers. That wire otherwise costs $5. Monster find where the scams are most profitable.

A Monster Cable protector is the same circuit selling in the grocery store for $7. Appreciate why you were looking in the wrong place. Monster Cable does not have and will not discuss a dedicated wire for that essential and required short connection to earth. Where must surge energy be diverted to? NIST defines that Monster Cable solution:
> A very important point to keep in mind is that your surge protector will
> work by diverting the surges to ground. The best surge protection in
> the world can be useless if grounding is not done properly.

One effective 'whole house' protector sells in Lowes for less than $50. Of course, your earthing must both meet and exceed post 1990 National Electrical Code. Why? A protector is only as effective as its earth ground.

[westom]

Originally Posted by Ted383 When I was looking into the things I'd need to learn to get my new plasma table set up, I expected certain things to be complicated...finding a surge protector/UPS was not one of them

I am an engineer who even had to design this stuff, suffered direct lightnings strikes, and did not even have damage to the protector.

Go to Lowes. Buy the Cutler-Hammer 'whole house' protector for less than $50. Install it. Upgrade earthing to meet and exceed post 1990 National Electrical Code earthing requirements. Do nothing to any other wiring. Have router protection superior to anything else suggested. This is what high reliability facilities do (ie your telco) to suffer hundreds of surges even from direct lightning strikes - and not have damage.

It only gets complicated and longer when you also learn why that is clearly the best suggestion posted.

Monster Cable has a long reputation of selling into scam markets such as speaker wire with polarity. They are selling $7 power strips and fancy paint even for $150. That profit margin is why a salesman may spend more time pushing a Monster Cable product than promoting the new TV.

[jimcolt]

My UPS is a 450VA unit...$39.95 @ Staples office supply. It solved all of my power related issues as well as some electrical noise related issues. The rest of the noise related issues were solved by driving a ground rod next to the machine and properly, yet very simply, grounding the frame of the machine, the slat bed and the plasma to a star ground point directlly at the ground rod.

Jim

Originally Posted by Ted383 When I was looking into the things I'd need to learn to get my new plasma table set up, I expected certain things to be complicated...finding a surge protector/UPS was not one of them My original plan was to buy a UPS. So I did. A got a Cyberpower from Best Buy, I think it was 425VA. When I moved the steppers the UPS alarm sounded and shut it down. I know a larger UPS would fix the problem but several people have told me (including PlasmaRoute) that the only way to guarantee component safety is to unplug them when not in use. But when you do that the UPS kicks in. I don't know if it's cool to do that every night. There are formulas to calculate the size UPS needed for a given application but being that my PlasmaRoute motion control box is "homemade" it does not have a label. All I know is it draws 20 amps. So then I figured just go with a good surge protector but that has it's complications too (see first post). Jim, What size is your UPS? .

[Ted383]

Thanks to all for your replies.

It's clear to me that this topic falls under the "black art" category. The ways of dealing with surge suppression and RF interference vary widely. After reading replies here and speaking to a friend who is an engineer for a high end home audio/video outfit I decided to go with this...

http://panamax.com:80/Products/Floor...IP-20A-EX.aspx

I tracked one down for $135. My friend has been using Panamax products for years tells me they are high quality.

I will pick up a cheap UPS at Best Buy and plug it into the panamax, then plug only the PC and THC into the UPS.

-ted


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[westom]

Originally Posted by Ted383 After reading replies here and speaking to a friend who is an engineer for a high end home audio/video outfit I decided to go with this... http://panamax.com:80/Products/Floor...IP-20A-EX.aspx

So he designed protectors? He suffered direct lightning stirkes with no damage? It is not a black art. The principles have been well proven for over 100 years. The point made repeatedly - a protector is not protection. A protector is simply a connecting device to earth. That Panamax has no such earthing.

NIST described that Panamax product:
> The best surge protection in the world can be useless if grounding is
> not done properly.

Why would you spend $135 for a protector that also sells in grocery stores for $7. Why would you spend $135 per appliance for inferior protection when the well proven solution costs about $1 per protected appliance?

It is only a black art when a scam is promoted. That Panamax has no earthing. Where does hundreds of thousands of joules get dissipated? Did he say? Did he discuss what is essential to protection? Upgrading your earthing?

The black art is to get everyone to forget what provides surge protection - earth ground. A protector is only as effective as its earth ground - as was understood even 100 years ago.

[Ted383]

Originally Posted by westom So he designed protectors?

No but his coworker has. And he agreed with my friends recommendation.
This is the set up...




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