The New Ground Cube and New Tamper Resistant Breakaway Nut
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Smart Grid Design (SGD) devotes extensive research to any product we offer. A key part of our research effort includes close follow up with all related people using our products. With this device's original design, CenterPoint Energy field gave feedback, we listened! CenterPoint Energy also tested prototypes of this design. We collected ideas from our customers, particularly linemen, inspectors, designers, engineers and management. This data played a significant role designing the greatly improved "New" Ground Cube Kit. This kit has gone through extensive analysis/prototyping and testing for over two years. We are now ready to share this highly evolved crime fighting solution with you, our valued customer. Together we can fight crime and strengthen our nation's electric grid!
Need sample? Contact Sales. We are proud of our products. We are equally proud of our stewardship. Knowing our customers experience is key to future purchases, we, like our products will work hard to serve you. Should you think we can improve our service in anyway - we listen. |
Ground Block
(figure 1) 
Tamper Resistant
Break-Away Nut 65 (figure 2) |
Specific issues/feedback given and resolved:
- Desired a stronger connection. Smart Grid Design doubled the amount of foot pounds required to break the head off the tamper resistant nut. This was developed under the guidance of Larry K., he also tested it and then approved it. Thanks Larry K.! (see figure 2)
Note: To reach the desired break strength it is no longer possible to machine a heavy duty 1/2" nut, It simply has too little metal. The new Tamper resistant nut is machined from bar stock our cost has increased slightly as a result for this component.
- Prevent pull through or stud breaking risk. The new design eliminates the issue by replacing the notched stud with a standard bolt. Howard W. played a major role in advising Mr. Lopez as he developed this component. Thanks Howard W.!
- The new part would be too costly to machine or cast. Yes and No. Machining would be "slightly" more costly than the original ground cube. We feel the improved performance and reliability would outweigh the nominal cost. The big surprise was the quality and great pricing found in investment casting. After recovery of upfront cost (mainly tooling for lost wax injection molds) the end cost will be basically the same price as the original ground cube. Mr. Mike P. tabled this concern. Thanks Mike p.!
(see figures 1,3,4)
- Desired a stronger connection. Smart Grid Design doubled the amount of foot pounds required to break the head off the tamper resistant nut. This was developed under the guidance of Larry K., he also tested it and then approved it. Thanks Larry K.! (see figure 2)
Note: To reach the desired break strength it is no longer possible to machine a heavy duty 1/2" nut, It simply has too little metal. The new Tamper resistant nut is machined from bar stock our cost has increased slightly as a result for this component.
- Prevent pull through or stud breaking risk. The new design eliminates the issue by replacing the notched stud with a standard bolt. Howard W. played a major role in advising Mr. Lopez as he developed this component. Thanks Howard W.!
- The new part would be too costly to machine or cast. Yes and No. Machining would be "slightly" more costly than the original ground cube. We feel the improved performance and reliability would outweigh the nominal cost. The big surprise was the quality and great pricing found in investment casting. After recovery of upfront cost (mainly tooling for lost wax injection molds) the end cost will be basically the same price as the original ground cube. Mr. Mike P. tabled this concern. Thanks Mike p.!
(see figures 1,3,4)
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Post investment
coating process (figure 3) |
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Post investment
coating process (figure 4) |
We at Smart Grid Design understand the importance of listening to our customers, particularly our nation's awesome linemen who install this hardware. The original ground cube relies on a notch in the stud to envelope or grasp the ground rod inside the ground cube. In early development studies of the original ground cube it was known the stud is subject to pulling through the ground rod or crack and break at the notch if excessive pressure was applied to it. However proper functional contact can be made at around 35 foot pounds, so the breakaway nut was designed to break-away at that measure of force. Feedback from the field expressed concern as they could impose movement (rotation about the centroid of the notched stud) by grabbing ground rod between the Ground Cude and earth the jiggling it from side to side. While it did not effect the function of the connection, linemen just rather things to feel tight. We listened. The new design eliminates the notched stud replacing it with a standard hex head bolt who's head grasp the ground rod inside the new ground cube. Less machining = less cost, more metal = stronger grasp. The new design basically eliminates the risk of pull through failure. The body of the original ground cube was machined and required tight tolerances to work correctly. The new Cube is a product of investment casting. This allows consistent specific tolerances without the cost or potential inconsistency of machining.
