Hi Thorangle
Usually the designer gives the UF in the project papers and its applied when has to be designe dthe distribution switchgear. In fact UF depends on the type of the load and installation (i.e. there is no target). It could vary too much. By using the UF you calculate the rated...
Check where are connected exactly the capacitor banks. If there are asynchr. motors with drives and/or DC motors with ddrives, some bad choise of capacitors, missing of reactors etc. can a reason for appearing of high level harmonics (5, 7 and 11 usually) and capacitors "reinforce" them.
Hi Jonnza
Try following sites:
http://www.mvps.org/visio/3rdparty.htm - good site
http://www.visiocafe.com/ - something could appear
Anyway, it's hard to find good stencils. If you have couple of free days try to create by yourself.
I suppose there was an arc between busbars in LV switchgear. Any short-circuit fault or overload would trip the CBs. If the inside air is not clean (even a close standing motorway could cause this) arc could appear and it will destroy the switchgear before any action from main CB.
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Hi Sparkodean
Everything said from other guys is correct. Just pay attention to high level harmonics. If you have frequency drives or softstarters for your motors they could create 5, 7 and 11 harmonics. In this case you will need reactors on the capacitor banks or harmonic filter...
Hi Suntop! Leave destructive answers:)) and take a look at my idea. I'm working in ABB for already 6 years and main activities are LV switchgears. To built your own switchgear system (type tested structure) will cost a lot of money, mainly for testing and preliminary desiging. I propose you to...
Sorry for the answer, but there is no way to do this. If you wnat use *.wmf files. For sure, any save of Visio file in CAD format will cause loss of formats. What
I do - I save the *.vsd file in *.pdf format, than using Adobe Acrobat I save it like *.htm or *.xml.
Hi! Use the fllowing definitions:
Short - circuit is the accidental or deliberate connection across a comparatively low resistance or impedance between two or more points of a circuit which usually have deiffering voltage. Therefore short circuit current Icc 0s the current in an electrical...