Hello,
Me and some of the colleagues are having a discussion about requesting electricty supplies from the Distribution Network Operator and stating the KVA rating of the supply.
The application is for street lighting, with the supply into a three phase feeder pillar, with circuits being...
Just about proceed doing some voltage quality analysis after the insertion of a CLR into a system ,however I thought it would be worth enquiring how others model this.
I was going to do it with the standard RLC component, with obviously R and C neglible/zero?
Any advice would be great on any...
Considering things like fault levels and the subsequent use of fault current limiters to combat high magnitudes I was wondering what issues does this introduce though?
Will having a big lump of resistance/reactance in the system will cause problems in the post-fault phase etc?!
This vaguely...
Does anybody know of any education institutes/luminaire manufacturers that offer a decent tunnel lighting course around the u.k.Alternatively any material that anybody may have that they would gladly pass on, would be gladly received, to supplement the BS EN 13201:2003 material I have.
Many...
Sorry Guys,
Just looking for some clarification regarding when you undertake cordination calcs, which current quantity do you use i.e. asymmetrical pk, asymmetrical RMS, or symmetrical pk/RMS when your defining your maximum fault levels against the device curves on either log paper or...
Can any of yous guys offhand, suggest a solution to detect phase-phase faults on a Dd0 system, where the lowest fault current due to arcing resistance, no inductive contribution is lower than the actual load current at that point? Obviously you cant simply set the current pickup on a standard...
Just a quick question guys, the rule of thumb that says the a CT should maintain the linear relationship between the reflections of the CT ratio for up to 20*the rated primary current.Is this with regards to the asymmetrical peak or RMS values? i.e. if I had a bus protected by a OC relay with a...
Any anybody give me some guidelines on discrimination when using MCB's as the PRAG manuals from the usual suspects dont mention anything about these devices for some reason. I was looking to use Terasaki TemBreak Series to protect a couple of 440 LV buses with have prospective asymmetrical peaks...
I was speaking to a colleague yesterday, when he mentioned that it is possible for a TX to have a greater inrush mutiplier when backfeeding through it, in order provide emergency measures.Has anybody else encountered this over there experience and any reason why it happens that the inrush...
Could somebody assist me in a quick sanity check please, following simulations results of a 13.8kV marine system, it was found that existed normal operating currents of around 15kA?!?!? on the bus following the secondary side, obviously to a guy who has limited experience even this seems...
Im fairly new to the protection division of the industry and have carried out a fault level anaylsis of a marine system, which ive to then cordinate the protection of the radial feeder.Ive found the Coordonaide program from S&C Company, but I was wondering do any of the more experienced power...
Im currently running some simulations for fault levels within a system, and using marine transformers that have X% of 16.1 and 12(1.4 and 3MVA respectively).Obviously the route of higher transformer impedences has to be explored to bring fault levels down.However as my practical experience is...
Im investigating the possibility of using PV arrays to feed some lighting columns all the name of sustainability, I was just wondering if anybody off the top of there heads may indentify some issues that may arise that i may miss further down the line.Or to reinforce any points that should be...
Does any of the experts in the protection field, who have more experience than myself know of a scheme to detect phase-phase faults on a unearthed system?
Thanking yous
Im considering protection of the above transformer in a unearthed LV system,and ive considered the percentage differential, balanced earth fault, wont be any Buccholz since its dry type, thermal relays and overcurrent for back-up functionality. But im wondering if ive managed to neglect...
Can anybody introduce myself to the joys of Parks Transformation, given that i have induction machine parmeters in both physical and per unit sense. This is first time i have encountered it ,as a new package has been brought in to the employers.
How does the physical parameters relate to the...
Can anybody introduce myself to the joys of Parks Transformation, given that i have induction machine parmeters in both physical and per unit sense. This is first time i have encountered it ,as a new package has been brought in.
How does the physical parameters relate to the matrices given in...
Do any of the experts have practical experience of marine power systems, with particular emphasis on protection?, i would love if someone could give me a pointer in the direction to a good website,book to illustrate the difference between utility protection techniques and the islanded system...
Does any of yous guy know of, a website , book etc that focuses on specifically marine electrical systems, in the magnitude of 13.8kV supply.Also will i'm at it do any of the experts possess any information regarding the protection of these systems, as the web is giving me no help at all.
Many...
