Power Factor at Unbalanced Load

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Anonymous Poster #1	Power Factor at Unbalanced Load 03/12/2015 7:50 AM
	Hi Friends, Please share your views on power factor imrovement at normal house having 3 Phase 10 or 15 KW connection.The department is considering billing units on KVAR basis now a days. The load condition is totaly unbalanced and may very upto 8 KW in one phase & nil in rest two phases. APFC available in market having single phase sensing relay will not work . Next option is APFC having three phase sensing relay and three phase capacitor banks , Please share your observations about working of three phase capacitor in unbalaced load conditions. Thanks and best regards,
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RAMConsult Guru Join Date: May 2007 Location: NYC metropolitan area. Posts: 3230 Good Answers: 444	#1 Re: Power factor at unbalanced load. 03/12/2015 8:08 AM
	Unbalance does not affect power factor, inductive/capacitive loads do. An APFC (Automatic Power Factor Correction/Capacitor/Controller) will do nothing for to correct the unbalanced loading, calling in a qualified electrician to spread your loads across all three phases will. btw- where are you located where three phase power is supplied to a "normal house"? __________________ “Tell me and I forget. Teach me and I remember. Involve me and I learn.” Ben Franklin.
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Wal Guru Join Date: Jun 2011 Location: Phnom Penh Posts: 4019 Good Answers: 102	#5 In reply to #1 Re: Power factor at unbalanced load. 03/13/2015 4:31 AM
	Reasonably normal in Oz for starters. __________________ Difficulty is not an obstacle it is merely an attribute.
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pnaban Guru Join Date: Jun 2010 Location: srilanka Posts: 2725 Good Answers: 5	#2 Re: Power Factor at Unbalanced Load 03/12/2015 11:51 PM
	Why did you request for a 3 phase supply,did the utility studied your connected load,did the utility do inspection and testing of installations or did you hire an approved engineer for certifying the installation,we don't know procedure adopted in your country(which).Do you use low pf equipment like welder,will utility allow it in domestic tariff?. __________________ pnaban
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1capybara Power-User Join Date: Mar 2012 Location: the sandbox Posts: 341 Good Answers: 6	#3 Re: Power Factor at Unbalanced Load 03/13/2015 12:55 AM
	does your house really have 3 phase? or is that a typo? __________________ BSEE but always learning
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Crabtree Guru Join Date: Jul 2007 Location: Commissariat de Police, Nouvions, occupied France, 1942. Posts: 2599 Good Answers: 77	#4 Re: Power Factor at Unbalanced Load 03/13/2015 1:50 AM
	It sounds as though you only need a single phase supply, Mildred. Forget imbalance. It is irrelevant. __________________ Good moaning!
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Anonymous Poster #1	#6 Re: Power Factor at Unbalanced Load 03/14/2015 7:58 AM
	The total load is fluctuating and can not be balanced in all three phases. The monthly KVAR readings are upto 1.5 times the KWH readings. Normal household equipments are being used. If I use APFC having three phase capacitors bank & it sense thorugh any of one phase having maximum load and same time rest two phases are at alomost nil load , will capacitors work normally?
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cuba_pete Guru Join Date: Dec 2010 Posts: 1895 Good Answers: 44	#7 In reply to #6 Re: Power Factor at Unbalanced Load 03/17/2015 10:03 AM
	Seriously... ...why do you have three phase power if two of the phases are almost nil? What type of service transformer does your "house" utilize? Again, your imbalance and your power factor are two different things. If you are concerned about power factor in a home and are only using one of three phases (odd, to say the least ) then you should pursue at-load power factor correction. Here's a link: At Load Power Factor Correction. I would suggest going to the panel(s) and moving some things around to deal with your imbalance if it really bothers you that much. Never heard of residential reactive power charges, either (three-phase, go figure).
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Wal Guru Join Date: Jun 2011 Location: Phnom Penh Posts: 4019 Good Answers: 102	#8 In reply to #6 Re: Power Factor at Unbalanced Load 03/18/2015 12:22 AM
	Normal, like fridges, airconditioners, flourescent lamps, vacuum cleaner, fans, computers, water pumps, washing machines, sewing sweatshops are all reactive loads. Never heard of KVAR metering in residential either . The days of mostly resistive loading has gone and it would all add up even in a non industrial environment. We may all soon be billed this way. As for the PC bank....I can't see it and the query is a bit messed up too....phase balancing is easy enough. __________________ Difficulty is not an obstacle it is merely an attribute.
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1capybara (1); Anonymous Poster (1); Crabtree (1); cuba_pete (1); pnaban (1); RAMConsult (1); Wal (2)

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