Interested to Buy Any Domain ? << Click Here >> for more details...
Answer Posted / guest
The Buchholz relay functions by making use of the liberated
gas inside the transformer due to an internal fault, to
actuate an alarm or trip the circuit breaker depending on
the seriousness of the fault. The virtue of buchholz relay
is that it detects an incipient fault i.e in the very early
stage itself before serious damage is done, whereas others
relays operate after the fault has occurred. Therefore
repair measures are simpler. Example of incipient faults are
short circuited core laminations, broken down core bolt
insulation, failure of inter turn insulation and consequent
local over heating , bad switch contacts and faulty joints etc..
The relay comprises a cast iron housing inserted in the pipe
connecting the transformer tank with the conservator tank.
It consists of two bucket mechanisms each connected to a
tilting head on which a mercury switch is mounted. The upper
assembly , traps small gas bubbles generated by an incipient
fault and if sufficient gas has been collected, it closes a
contact and sounds a hooter in the control panel in the
SUBSTATION. The lower assembly which is directly in the path
of the connecting pipe operates when there is a serious
internal fault like a short circuit between phases , coils
or turns, earth fault, arcing or puncturing of bushing
insulator inside the tank. This liberates a considerable
amount of gas, and the displaced oil and gas surge through
the connecting pipe, and impinge upon a deflection plate
fixed on the lower assembly in line with pipe. This tilts
the Mercury switch which in line with the pipe. This tilts
the Mercury switch which in turn trips the circuit breakers.
The buchholz relay also detects accumulation of air on
account of low oil level, or faulty oil pumps. A per cock is
provided on the top of the housing to draw samples of
accumulated gas for analysis. An inspection window shows the
amount of gas which has accumulated. Provision is made for
manual operation on the alarm and tripping mechanisms to
facilities testing. A better method is to pump air through
the pet cock
Ref- Dr G.V Rao Phd
If any other result please send to my id -
mastalinprabu@gmail.com
With thanks
M.STALIN
| Is This Answer Correct ? | 2 Yes | 1 No |
Post New Answer View All Answers
What are the components connected in between the power supply coming from an electric pole to HT & LT Panels in a large commercial building or how the power supply connected from Electric pole to Transformer & then to the HT & LT panels of a building? Please send me answers via mail, my id is yogiagarwal@gmail.com. If possible, please give a line diagram.
WHY IS THE EARTH FAULT CURRENT ALWAYS LESS THAN THE NORMAL CURRENT??
HOW TO SELECT THE COPPER CABLE SIZES OF MOTORS,TRANSFORMERS?
how the phase convertor changes the no. of phases
How to calculate capacitor bank value to maintain unity power factor with some suitable example?
what is a composite error in current transformers, why occurs & in which it will occur i.e, either metering ct/ protection ct
what is the minimum clearance between a 11KV 150KVAR capacitor cell and series reactor.can a series reactor can be mounted in the same structure of the capacitor cells structure
WHY DO VOLTAGE TRANSFORMERS FAIL DURING EARTH FAULT IN THE DELTA CONNECTED 6.6KV ELECTRICAL SYSTEM
What do you mean by dependent and independent voltage sources?
what percent do you derate your copper wire when you change from copper buss to copper wire
i need previous entrence exam papers of nhpc.
size of condotory fron voltage level
what is the earth current,reverse power,electrical trip generator short circuit,low voltage, high voltage please discribe me
how to control the speed to switched reluctance motor
List examples of voltage source?
