Interested to Buy Any Domain ? << Click Here >> for more details...
what is the difference between LPF and UPF wattmeter and
where it is used.
- 7 Answers
- 78816 Views
- I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / maniveer
LOW POWER FACTOR(LPF) & HIGH POWER FACTOR(UPF)
In open circuit test the secondary winding of transformer is kept open.As the secondary side is open, the entire coil will be purely inductive in nature.So the power will be lagging due to inductive property of the circuit. So LPF(Low Power Factor) Wattmeter is used in OPEN CIRCUIT TEST of Transformer.
In short circuit test the secondary winding of transformer is short circuited. As secondary side is short circuited the entire coil will be purely resistive in nature.So the power factor will be unity. So UPF(Unit Power Factor) Wattmeter is used in SHORT CIRCUIT TEST of Transformer.
| Is This Answer Correct ? | 258 Yes | 30 No |
Answer / venkata krishna
LPF wattmeter is used for measuring power in highly
inductive circuits & UPF wattmeter is used for measure power
in resistance circuit in which the power factor ranges from
0.5 to unity.
| Is This Answer Correct ? | 126 Yes | 21 No |
Answer / potnur hemarao
Lpf is used in power measuring in high inductive circuit and upf is used in power measuring in resistance circuit which power factor ranges 0.5 to unity
| Is This Answer Correct ? | 44 Yes | 8 No |
Answer / nitish kennedy
Low Power Factor wattmeters are specially designed to measure power at low power factor .
Ordinary wattmeters (i.e. UPF) are not accurate in measuring power at low power factor beacuse of -
low deflecting torque.
error due to inductance of of pressure coil is large at low power factor.
So some modifications are done in LPF wattmeters-
low value of pressure coil resistance to increase the torque.
pressure coil current is compensated using compensating coil.
capacitor is connected in pressure coil to reduce the error due to pressure coil inductance.
control torque is made very small.
| Is This Answer Correct ? | 5 Yes | 0 No |
Answer / k.prakashchandra
LPF -low pf UPF- unity pf.In lpf meter pf compensation is
done and is accurate at the specified low pf.
| Is This Answer Correct ? | 22 Yes | 33 No |
Answer / suresh
HERE LPF USED TO measure the low current & UPF is used to measure the high current. Then low pf and unity power factor
| Is This Answer Correct ? | 10 Yes | 26 No |
How can we choose the rating of submersible motors
what is meant by oil filled power & distrubution transformer ? if anybody know the link of detail about above transformers means plz send it i have interview on this week ? plz help me
What is the universal motor?
name the types of insulatter?
what is the working principle of a DG Set, Alternator, & exiter
how much watts are equal to one unit of energy meter?
how to interlock 3 incomer-ACB,1 buscoupler ACB,... pls answer this question and if possible send me the ckt diagram..haifriends2910@gmail.com
HOW TO CALCULATE THE ILLUMINATION IN INDOOR LIGHTING?
how can we change the supply frequency?
What happens to the synchronous generator when reverse power is given to it?
I'm looking for a mnaual set for a Teradyne J750. Softcopy would be preferred but I'll take what I can get.
What is the name of powder which is used in inner side of a cable? and purpose?
-
Civil Engineering (5086) - Mechanical Engineering (4456)
- Electrical Engineering (16639)
- Electronics Communications (3918)
- Chemical Engineering (1095)
- Aeronautical Engineering (239)
- Bio Engineering (96)
- Metallurgy (361)
- Industrial Engineering (259)
- Instrumentation (3014)
- Automobile Engineering (332)
- Mechatronics Engineering (97)
- Marine Engineering (124)
- Power Plant Engineering (172)
- Textile Engineering (575)
- Production Engineering (25)
- Satellite Systems Engineering (106)
- Engineering AllOther (1379)
