What is ONAN/ONAF1/ONAF2 for transformer cooling
Answers were Sorted based on User's Feedback
Answer / p.aruna devi
ONAN -Oil natural air natural
ONAF-Oil natural air force
Is This Answer Correct ? | 228 Yes | 13 No |
Answer / gowhar
The above answer is true.Moreover ,there is a two stage
forced cooling in some of the transformer
(ONAN/ONAF1/ONAF2.on First stage forced cooling(ONAF1) the
MVA rating increses 33% of the actual rating and on second
stage cooling(ONAF1) MVA rating increases to 66% of the
actual rating.
Is This Answer Correct ? | 98 Yes | 34 No |
Answer / shashank
ONAN type cooling:
The generated heat can be dissipated in many ways. In case
of smaller rating of transformers, its tanks may be able to
dissipate the heat directly to theatmospheric dry while
bigger ratings may require additional dissipating surface
in form of tubes/ radiators connected to tank or in the
term of radiator tank. In these cases, the heatdissipation
is form transformer oil at atmospheric air by natural
means. This form of cooling is known as ONAN (Oil Natural,
Air Natural) types of cooling.
ONAF type of cooling:
For further augmenting the rate of dissipating of heat,
other means such as fans blowing air on the cooling
surfaces are employed. The forced air takesaway the heat at
a faster rate, thereby giving better cooling rate than
natural air. This type8
of cooling called ONAF (Oil Natural Air Forced) type of
cooling. In this coolingarrangement, additional raring
under ONAN condition viz. after shutting off fans,
isavailable, which is of the order of 70-75%.
Is This Answer Correct ? | 41 Yes | 2 No |
Answer / abdullah ibrahim
The generated heat can be dissipated in many ways. In case
of smaller rating of transformers
Is This Answer Correct ? | 10 Yes | 0 No |
what is the minimum insulation resistance for HT AND LT motor ?
what r the earthing required for commissioning of D.G set?
Why we are mention U1, V1, and W1 in primary side of transformer give technical reason
WHICH SUPPLY IS BETTER FOR 4 MW LOAD. 1)TO TAKE NEARER AVAILABLE 11 KV SUPPLY OR 2)TO TAKE 33 KV SUPPLY WHICH IS AVAILABLE AT 10 KM DISTANCE BY INVESTING NEARLY 50-60 LACKHS
For 35 HP motor how much amount of capacitor should be on in kvr to reduce the current bill
WHAT IS THE SHOPE TESTING
What is Plank's Law?
why h parameter are called as hybrid parameter?
all the technical question with answers pleas send your email id ramar_eee@yahoo.com
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 Procedure the procedure to select CT's & PT's in 66kV and above substation?
3 Answers Infotech, Vijai Electricals,
In the UVR(Under Voltage Relay) there is a knob for the hysteresis setting. what is this setting? its threshold is given from 5% to 50%. please help me....