HF grounding

[zoama]

I hate to make this thread any more complicated... but here goes. Multiple ground rods don't cause a problem when they're all bonded together. That problem arises when you have an isolated ground (power comes from the service panel but goes to a separate ground that isn't tied back to the panel).

In the case of our welders, we're adding a shorter path to ground that is bonded to our service panel ground through the welder's chassis and will not cause a problem.

[hesstx]

I hate to make this thread any more complicated... but here goes. Multiple ground rods don't cause a problem when they're all bonded together. That problem arises when you have an isolated ground (power comes from the service panel but goes to a separate ground that isn't tied back to the panel).

In the case of our welders, we're adding a shorter path to ground that is bonded to our service panel ground through the welder's chassis and will not cause a problem.

What Im getting out of this is that as long as the rods come attach to the panel it should be OK I ave been running this way for 5 years and we get lots of lightning but only on hit close and that was the micro tower an acre away

[hesstx]

I knew I had seen this somewhere. its in the manual for the Ever Last 205 pro
"The ground bolt on the rear of the machine is designed to help eliminate High Frequency interference from the machine. Ground the Case bolt to a separate wire to a metal ground rod outside the facility that is in moist soil. Occasionally multiple ground point are required. DO Not ground back to the electrical circuit ground as harmful HF feedback can occur. Do not attach HF ground directly to table, cart, electrical circuit of panel box!"

That adds more confusion

[CGCINC]

Question:
I have a concrete floor where my welder is located. The building is covered in metal but the framing is wood so the metal does not go all the way into the ground. Would attaching a small chain to the HF ground and letting it touch the concrete floor do anything at all? I could run the chain through some rubber hose from the welder to the floor so it does not ground out on the cart.....!?!?!

[hesstx]

Question:
I have a concrete floor where my welder is located. The building is covered in metal but the framing is wood so the metal does not go all the way into the ground. Would attaching a small chain to the HF ground and letting it touch the concrete floor do anything at all? I could run the chain through some rubber hose from the welder to the floor so it does not ground out on the cart.....!?!?!

if you steel is in the ground why could you just allargatter (sp) clip if to the steel post? if your steel in not in the ground could you place a ground rod outside and attach that to the post.. kind of like the old lighting rod on a roof

[zoama]

Question:
I have a concrete floor where my welder is located. The building is covered in metal but the framing is wood so the metal does not go all the way into the ground. Would attaching a small chain to the HF ground and letting it touch the concrete floor do anything at all? I could run the chain through some rubber hose from the welder to the floor so it does not ground out on the cart.....!?!?!

Nope, wouldn't help. If you don't have any sensitive electronics around when you're welding then don't worry about it. It'll be fine.

[EricCox]

Question:
I have a concrete floor where my welder is located. The building is covered in metal but the framing is wood so the metal does not go all the way into the ground. Would attaching a small chain to the HF ground and letting it touch the concrete floor do anything at all? I could run the chain through some rubber hose from the welder to the floor so it does not ground out on the cart.....!?!?!

No, you wouldn't want to do this - it would not be a electrical ground because concrete is not a conductor.

If you're having problems when you light up your welder caused by the HF (lights flickering, computers rebooting, neighbors complaining about weird lines on their TV sets, etc), here is what you can do for a damn near perfect ground - my dad did this when he used to build high power ham transmitters: drive multiple ground rods into the earth around the perimeter of your shop/garage. Run wires through the walls into the shop, then connect them to one large bare copper wire that runs around the inside perimeter of the shop. Connect this wire to the same ground that the panel uses (not to the panel itself - best to leave that alone). Connect the chassis ground of all of your outlets to this bare ground wire. Make sure all connections are clean before putting them together, and then spray them with a good corrosion inhibitor. (Personally I would start out with 1 rod, and keep adding them until the problems go away - it's a lot of work)

This provides the shortest path to ground for High Frequency, low power signals (interference), while still providing proper grounding for low frequency high power signals (electrical power). At 60Hz the panel ground is fine even though it may not be the shortest path. The reason to use a short-path to ground is that HF signals are more likely to "leak" out of a long ground path, effectively turning it into an antenna, which puts nasty lines on your neighbors TV sets and static on their radios.

(My dad once had to buy the guy next door a new TV set because a particularly high-power transmitter leaked enough during testing that it overloaded the amplifiers in the guy's TV and let the smoke out)