In one of my previous projects we had three transformers working in parallel.This required a synchrocheck relay to check the magnitude of Voltage, phase angle and frequency. However , is it possible to run a generator and Distribution transformer permanently(The generator is not used as a...
Thanks both of you..I do not think there could arise a problem of rain or moisture since we are talking about a remote Petroleum Development area in the Middle East(Middle of the desert).Also this one is for a Chiller Plant for Accomodation blocks with little possibilities for contaminants,acid...
Dear Waross,
Thanks for your reply..But i missed your point completely regarding glycol paint. Hope thats a joke..!
1.Tha Switchgear Panel gland plate is aluminium.My cable is 1cx630 sq.mm,AWA 3 runs per phase. I'm planning to use Brass Cable Glands for this cable.I will be running these cables...
Hi all,
I have a simple but important question.
Can we use Brass Glands for Aluminum Wire Armoured SIngle Core Cables ?? The gland plate material is Aluminium.
No I don't have surplus cable..But out of ignorance we usually order four core cables for Motors as well.I wanted to confirm whether its right technically..Commercially speaking its a waste of money.
The Four Core Cable as I mentioned above refers to 4 insulated similar conductors.It is usually used for 3ph Neutral Applications.An Yellow Green Earth Cable is run separate for the purpose of earthing.
My only doubt is whether it I can I Leave one core(meant for neutral) unused when im feeding...
Hi..
1. Is it recommended to use 4 Core Cables for '3 phase applications without neutral'? Then the neutral will have to be left unterminated at either ends right..? Also would it lead to any induced currents in the neutral Core..?
You might have heard of LV Panels with Forms of separation Form 2 and Form 4.Our Consultant has proposed a hybrid variant..with Form 4 Incoming section(2 incomers+1 buscoupler) and form 2 for outgoings(Hvac Loads)... Is this a common arrangement??I presume the only benefit will be cost savings..?
How to size such fuses..? Should we consider starting current also while sizing these fuses..? or is it FLC? I am confused because my consultant has asked me to confirm a 250 A upstream Switch fuse isolator for 226 A FLC downstream panel...
I would like to know weather fuses used in motor starters are time delay fuses.Please find the specific fuse type we have used in the attached Image..Are these fuses time delay fuses..?
ScottyUk,
I have done my bit of searching & researching..I have checked the time current characteristic of the breaker..from that it should hold even higher currents..i also send a technical query to schneider regarding this..But the consultant has advised us to use starters of the pump hence...
Thanks a lot ScottyUK..It has always been like this for me..I cant find a new job due to lack of experience...and fed up asking senior engineers for guidance..they wont help as they don't want to take responsibility..
Thanks Lionel & X49..
When I have both Chillers,one pump n minor load running Total FLA is 2145..at this time if the pump starts ,the total current will be 2145+555=2700A..Im just wondering if this could be a problem for the transformer..Also can the 2500 A Breaker withstand this without...
http://hto.power.schneider-electric.com/CBT/Apps/CurveCoordination.aspx?lang=en-GB®ulation=EuropeCenelec#Discrimination
I got the curves in the above link for model: Masterpact NW25H2 Micrologic 6.0 A..Can you confirm weather this can hold 2700 A for 10/20 sec?
I already downloaded curve direct..But Im not sure as to the conclusion from that.Y axis it has time in sec..and x-axis they have current..So I need to check the intersection of 2600 A and note how mucg time it can hold right? Can you check out n tell me?
The transformer size is 1600 KVA.With rated amps 2100 Amps...The breaker is 2500A 4P,drawout motorized acb with micrologic trip unit with O/L,S/C & E/F protection-100 KA/1sec,make:schneider elctric,Model:NW25 H2+Micrologic 6.0 A..The locked rotor starting time of pump is 10 sec as per motor data...
The transformer size is 1600 KVA.With rated amps 2100 Amps...The breaker is 2500A 4P,drawout motorized acb with micrologic trip unit with O/L,S/C & E/F protection-100 KA/1sec,make:schneider elctric,Model:NW25 H2+Micrologic 6.0 A..The locked rotor starting time of pump is 10 sec as per motor data...
I have 45 KW Chilled water constant flow pump.It was earlier proposed to start it by DOL.But now due to limitation in incomer breaker size and transformer capacity we have to go for another method of starting.Which method can I use so that I can keep starting current to the least possible...
It is highly recommended that you take support of the sfc manufacturer or their local agent in Abudhabi.Hope they are competent enough to solve this issue. Also consult the FCU factory of the possible effects of using 60 Hz instead of 50 Hz. You might be knowing the outcome, but better to ask...