CNC: IP ratings of the electricals in a CNC machine
How much water and dust can your CNC electricals withstand ?
The IP (Ingress Protection) rating is very a important aspect of the electrical equipment (cabinet, motors, switches, etc.) used in CNC machines. The equipment has to work in the midst of dust and coolant, and the IP rating tells you how well it can withstand this.
The IP rating is defined by the IEC standard 60529 (IEC=International Electrotechnical Commission). It is a 2 digit number.
The first digit is the protection that the equipment’s enclosure provides against entry of solid objects and dust into the equipment. The second digit is the protection against entry of water (meaning coolant, in a CNC machine).
E.g., an electrical socket may be IP20, just appropriate to prevent you shoving your finger into it. The spindle motor may be IP40, the axes servo motors may be IP67, the electrical cabinet may be IP54.
When two machines of the same size and look similar, the IP rating of parts is one of the reasons that one costs X and the other costs 2X. Higher protection costs more money, but makes the machine more reliable. The IP ratings may one of the reasons that the cheaper machine breaks down every 2 days. When you are planning to buy a machine, look at the quality of the electricals (apart from the class of bearings, the grade of Cast Iron used, etc.)
Text and pics. source: CADEM NCyclopedia multimedia CNC training software.
Windmills – how are these monsters erected ?
I’ve been seeing windmills in action around the country, and have often seen them being transported on highways. Like the ones in these pictures that I saw last month, on the Bangalore-Hyderabad NH7, 150 km. from Bangalore.
I’ve always wondered how these monstrous things were actually erected, and the only way to actually satisfy my curiosity would have been to go and stand at a windmill site for 4 hours and see the process.
Till I hit upon the lazy city-slicker’s solution. I compressed my 1-day knowledge-gathering (drive 3 hours, watch for 4 hours, drive back 3 hours) into a few minutes of sitting on my butt and watching these videos on my laptop (both of windmills in the UK).
Lovely 2.5 minute time-lapse video https://www.youtube.com/watch?v=9u_EyxSVL5o
Another (10 minute) video that shows the whole process – transporting + erection https://www.youtube.com/watch?v=r0DZUDQyw_0