I'm not sure I agree with the "proprietary" part of the comment "Ethernet IP used in Allen Bradley processors is a propritary "language"." At one time, this statement may have been true; however, today Ethernet/IP is an open standard (this does not mean the specification is free) managed by ODVA...
Hello all,
I am investigating the application of a "power on" indicator lamp for machine control. I am interested in any code references in any standard that explicity discusses the application.
Specifically:
1) Is a "power on" indicator light required for machine control?
2) Is a "power...
Fundamentally NFPA standards including NFPA 79 are national in scope. The interpretation of the standard does not depend on the locale - the code is the code and the intent is the intent; however, jurisdictions may modify the standards (typically by adding regulation) at their discretion. This...
Cheers All,
Please forgive my lack of world travel!
Is 230V 1[Φ] the most common distribution system for commercial/residential applications within the EU and UK?
What is the prevalence of type TN and TT distribution systems in the EU and UK with respect to industrial, commercial, and...
Thanks for all the comments so far. Don't quit on me yet though. How about the multiple VFD's on one isolation transformer and related questions?
Also, another aspect of the machine installation is the hatchery often has GFCI (RCD) protection for the receptacle powering the machine, so it is...
The machines serve both markets (US and Europe) and as such a one size fits all design is being implemented. It is possible the GFCI tripping issue is in the US only. The history of the machines is new for me. The machines are used in hatcheries.
I find it interesting that RCD's in Europe trip...
[b]DickDV:{/b]
My thoughts exactly on the carrier frequency. However, a Fluke 360 Leakage Current Clamp was used to measure the current in the PE (ground) conductor at the different carrier frequencies. At the high carrier freq, the current in the PE (ground) conductor decreased! I don't quite...
Hello all,
The application consists of four 1/2HP 115V 1[Φ] In / 230V 3[Φ] Out VFD's powering 1/2HP gearmotors that drive simple conveyors. The conveyors are dual narrow urethane V-belts riding on steel guides carrying egg flats. The VFD's will be loaded at approximately 75%. The...
Synchronous (Timing) belts require proper "engineering" for a successful installation. For example, some belt manufacturer's offerings such as the Gates PowerGrip GT2 have proprietary tooth profiles requiring matched pulleys. The Gates website has "design manuals" available for download. The...
The following article briefly discusses smart grid security and mentions a NIST document that is highly relevant to the security discussion.
The article:
http://electronicdesign.com/article/power/smart_grid_design_opportunities_extend_from_the_meter_to_the_mercantile_exchange.aspx
The NIST...
I have seen a small knitting plant (6 - 8 machines) being supplied by a phase converter (can't remember if it was static or rotary) keep running when the entire plant was single phased (due to a failure in the wiring to the phase converter). All the machines kept running until the machine with...
Yes, thanks everyone for the enlightening discussion, and especially to rbulsara and prc. The information presented has diminished my cynicism as usually happens when factual information testifies against hearsay anecdotal evidence (I am assuming everyone is being truthful).
Also, I regret my...
