Does a flexible cable carrying 30 VDC (Discrete Signal) Fall under NEC 400.8 or NEC 725? Is NEC 400.8 written for temporary and extension cords that carry 120 VAC and above? Is NEC 725 for power limited cables. I mounted a flexible cables to the wall. The cables are discrete 30 VDC that...
I have to balance the pH in a wet Scrubber to the tune of 7.0 to 7.5. The acid is coming from Sulfur in the air stream. The caustic is costing me a furtune. about 1 mil per year. Does anybody have any suggestions on how I can reduce this cost.
I was asked by the boss to purchase or build a PLC I/O test panel. Some people call them PLC trainers. I’ve seen many of them sitting in other PLC programmers offices. For the most part, most of them are home made and are just pieces of wood or a NEMA box with holes drilled out so that the...
I have a Siemens S7-315 that was password protected from a previous employee. The employee cannot be found. Does anybody know how to get around this password. Also I was told the this ex-employee used symbol tables when programming. Does anybody know how I can cross reference the ladder bits...
