What is the normal indication on a megger when checking insulation?

What is the normal indication on a megger when checking insulation?
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infinity
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Related questions

What is a normal indication on a megger when checking insulation?

Description : What is a normal indication on a megger when checking insulation?

Last Answer : Infinity.

An operator tells you that flow indication is more, How would you start checking?

Description : An operator tells you that flow indication is more, How would you start checking?

Last Answer : First flushing the transmitter. Flush both the impulse lines. Adjust the zero by equalizing if necessary. If still the indication is more then. • Check L.P. side for choke. If that is clean then. • Check the leaks on L.P. side. If not. • Calibrate the transmitter.

An electronic measuring device that provide instantaneous visual indication of voltage excursions

Description : An electronic measuring device that provide instantaneous visual indication of voltage excursions

Last Answer : oscilloscope

Resistance measuring instrument particularly used in determining the insulation resistance

Description : Resistance measuring instrument particularly used in determining the insulation resistance

Last Answer : Megger/Megaohmmeter

Insulation resistance is measured by which meter?

Description : Insulation resistance is measured by which meter?

Last Answer : megger

Which of the conditions listed will indicate the need to clean the insulation on the windings of an electric motor? A. Higher than normal operating temperature. B. Excessive vibration at normal speed. C. Sparking at the brushes. D. High megger readings.

Description : Which of the conditions listed will indicate the need to clean the insulation on the windings of an electric motor? A. Higher than normal operating temperature. B. Excessive vibration at normal speed. C. Sparking at the brushes. D. High megger readings.

Last Answer : Answer: A

When troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by _______________. A. a resistance reading of 'infinity' on an ohmmeter B. charred insulation and/or a blown control fuse C. a reading of 'zero' on a megger from one of the coil's leads to ground D. a higher-than-normal voltage reading across the winding

Description : When troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by _______________. A. a resistance reading of 'infinity' on an ohmmeter B. charred insulation and/or a blown ... of the coil's leads to ground D. a higher-than-normal voltage reading across the winding

Last Answer : Answer: B

What do you call an oscilloscope that uses sampling techniques in processing signals having frequencies beyond its normal capabilities?

Description : What do you call an oscilloscope that uses sampling techniques in processing signals having frequencies beyond its normal capabilities?

Last Answer : sampling oscilloscope

A useful instrument for checking A.C. motor performance by measuring possible unbalanced currents is the _____________. A. hand or battery-operated megger B. vibrating-reed frequency meter C. hook-on voltmeter-ammeter D. D'Arsonval iron-vane probe

Description : A useful instrument for checking A.C. motor performance by measuring possible unbalanced currents is the _____________. A. hand or battery-operated megger B. vibrating-reed frequency meter C. hook-on voltmeter-ammeter D. D'Arsonval iron-vane probe

Last Answer : Answer: C

The electrician reports to you that he has obtained low (but above 1 megohm) megger readings on the windings of a deck winch motor. Upon checking the records of that motor, you find the readings have consistently been at that level for the last six yea A. motor be replaced B. windings be dried C. windings be cleaned D. readings are acceptable

Description : The electrician reports to you that he has obtained low (but above 1 megohm) megger readings on the windings of a deck winch motor. Upon checking the records of that motor, you find the readings have ... yea A. motor be replaced B. windings be dried C. windings be cleaned D. readings are acceptable

Last Answer : Answer: D

As a general rule, the first troubleshooting action to be taken in checking faulty electric control devices is to _____________. A. draw a one line diagram of the circuitry B. test all fuses and measure the line voltage C. take megger readings D. insulate the apparatus from ground

Description : As a general rule, the first troubleshooting action to be taken in checking faulty electric control devices is to _____________. A. draw a one line diagram of the circuitry B. test all fuses and measure the line voltage C. take megger readings D. insulate the apparatus from ground

Last Answer : Answer: B

Routine maintenance of dry-type transformers should include ______________. A. preventing the entrance of water from broken pipe lines steam lines B. keeping protective surfaces and insulating bushings free of dirt and conductive debris C. periodic testing of insulation resistance with a megger D. all of the above

Description : Routine maintenance of dry-type transformers should include ______________. A. preventing the entrance of water from broken pipe lines steam lines B. keeping protective surfaces and insulating bushings free of ... debris C. periodic testing of insulation resistance with a megger D. all of the above

Last Answer : Answer: D

Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Description : Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Last Answer : Answer: D

The need for insulation cleaning may be determined by _____. A. visual inspection for dirt accumulation B. high megger readings C. low operating temperature D. the time period since the last cleaning

Description : The need for insulation cleaning may be determined by _____. A. visual inspection for dirt accumulation B. high megger readings C. low operating temperature D. the time period since the last cleaning

Last Answer : Answer: A

Electrical machinery insulation will break down more rapidly due to _________________. A. low loading of motors and generators B. frequent megger testing C. high temperatures and vibration D. high operating frequencies

Description : Electrical machinery insulation will break down more rapidly due to _________________. A. low loading of motors and generators B. frequent megger testing C. high temperatures and vibration D. high operating frequencies

Last Answer : Answer: C

Routine maintenance of a ship's service alternator should include ______________. A. changing the pedestal bearing insulation yearly B. megger testing of all rectifying diodes C. lubricating excitation slip rings D. periodic cleaning of the air filters or screens

Description : Routine maintenance of a ship's service alternator should include ______________. A. changing the pedestal bearing insulation yearly B. megger testing of all rectifying diodes C. lubricating excitation slip rings D. periodic cleaning of the air filters or screens

Last Answer : Answer: D

A generator has been exposed to water and is being checked for its safe operation. Therefore, it is necessary to _______________. A. check for shorted coils with a growler B. take moisture readings with a hydrometer C. test insulation values with a megger D. ground the commutator, or slip rings and run it at half load for 12 hours

Description : A generator has been exposed to water and is being checked for its safe operation. Therefore, it is necessary to _______________. A. check for shorted coils with a growler B. take moisture readings with a ... a megger D. ground the commutator, or slip rings and run it at half load for 12 hours

Last Answer : Answer: C

What is the procedure for using a megger to check the insulation of a conductor?

Description : What is the procedure for using a megger to check the insulation of a conductor?

Last Answer : Connect one lead to the insulation and one lead to the conductor. Turn the handcrank until it starts to slip. Note the reading

Why is a Megger used for insulation test and not a multi meter?

Description : Why is a Megger used for insulation test and not a multi meter?

Last Answer : With a megger,a voltage of not less than 500 volts DC is used for testing the insulation resistance of windings. With a multi-meter, the voltage used is not more than 3-volts DC. Megger uses high impedance testing and is therefore more accurate than a multi-meter

A megger is to measure insulation resistance of a cable. The cable should be connected to

Description : A megger is to measure insulation resistance of a cable. The cable should be connected to   (a) Battery (b) DC supply (c) AC supply (d) No supply  

Last Answer : majorly in DC as well as AC......but ans is Battery

To measure insulation resistance of equipments of voltage rating upto 440 V the megger generator must generate...

Description : To measure insulation resistance of equipments of voltage rating upto 440 V the megger generator must generate   (a) 220 V (b) 440 V (c) 500 V (d) None of these 

Last Answer : 500 V

An Operator Tells You That Flow Indication Is More? How Would You Start Checking?

Description : An Operator Tells You That Flow Indication Is More? How Would You Start Checking?

Last Answer : 1. First flushing the transmitter. Flush both the impulse lines. Adjust the zero by equalizing if necessary. If still the indication is more then. 2. Check L.P. side for choke. If that is clean then. 3. Check the leaks on L.P. side. If not. 4. Calibrate the transmitter.

What is a filter used for ?

Description : What is a filter used for ?

Last Answer : The half wave and full wave signals are pulsating D . C . voltages. The use of such voltages is limited to charging batteries, running D. C. motors, and a few other applications. What we really ... voltage from a battery. To get a constant voltage from this, we can use a capacitor input filter. 

What is Zener Diode ? What is a voltage Regulator ?

Description : What is Zener Diode ? What is a voltage Regulator ?

Last Answer : The breakdown region of a p n diode can be made very sharp and almost vertical Diodes with almost vertical breakdown region are known as Zever Diodes. A Zener diodes operating in the breakdown ... VOLTAGE REGULATOR : The output remains constant despite changes in input voltage due to Zever effect.  

What is transistor ? What are the different types ?

Description : What is transistor ? What are the different types ?

Last Answer : A transistor is a three lagged semi conductor device. Basically a transistor means (transfer - resister). Whether the transistor is pnp or npn it resembles two diodes (back to back). The one of the left ... transistor : Emitter - Base - Forward Bias. Collector - Base - Reverse Bias. 

What is CB, CE and CC configuration ?

Description : What is CB, CE and CC configuration ?

Last Answer : Buffer : A device or a circuit used to isolate two pt'ne circuits or stages. The emitter follows is a example of buffer. Alpha = IC / IE Beta = IC / IB

How will you test a transistor with a multimeter. ?

Description : How will you test a transistor with a multimeter. ?

Last Answer : 1. Emitter +ve of meter and Base -ve output = Low resistance 2. Emitter -ve of meter and base +ve output = High resistance. 3. Collector +ve and Base -ve output = Low. 4. Collector -ve and base +ve output = High. Emitter : Collector = High Resistance. PNP : Opposite Results. 

What is a thyristor ? What are its uses ?

Description : What is a thyristor ? What are its uses ?

Last Answer : A thyristor is a special kind of semi conductor device that uses internal feedback to produce latching action. Use : Used for controlling large amounts of load power in motors, heaters, lighting systems etc ... the latches like a open switch. This latch will always stay in open or close position.  

What does a transmitter output start from 3-15 psi or (0.2 - 1 Kg/Cm2) or 4 - 20 ma. etc. ?

Description : What does a transmitter output start from 3-15 psi or (0.2 - 1 Kg/Cm2) or 4 - 20 ma. etc. ? 

Last Answer : The transmitter output stance from what is known as "live zero". This system has specific advantages : 1. The systems automatically alarms when the signal system becomes inoperative. ... transmitter operating, but transmitting a zero measurement and a failure, in the signal system. 

What are Intrinsically safe system ?

Description : What are Intrinsically safe system ?

Last Answer : Intrinsic safety is a technique for designing electrical equipment for safe use in locations made hazardous by the presence of flammable gas or vapors in air. "Defn. :" Intrinsically safe circuit is ... , unfortunately, been adopted in all countries. However two sets of codes in common use are.  

What is feed back control ? What is feed forward control ? Discuss its application ?

Description : What is feed back control ? What is feed forward control ? Discuss its application ?

Last Answer : Feed back control: Feed back control involves the detection of the controlled variable and counteracting of charges its it's value relative to set point, by adjustment of a manipulated ... controller for a particular process application, two factors time and gain must be considered.    

What is Furnace Draft control ?

Description : What is Furnace Draft control ? 

Last Answer : Balanced draft boilers are generally used negative furnace pressure. When both forced draft and induced draft are used together, at some point in the system the pressure will be the same as that of atmosphere. ... have is a very slight (about 0.1" H20 ) negative pressure of the top of furnace.  

What is the difference the a wheatstone bridge and a potentiometer ?

Description : What is the difference the a wheatstone bridge and a potentiometer ?

Last Answer : The difference between a potentiometer and a wheatstone bridge measuring instrument is that potentiometer is a voltage measuring instrument and wheatstone bridge is a current measuring instrument. 

What is the specialty of thermocouples lead wires ?

Description : What is the specialty of thermocouples lead wires ?

Last Answer : They should be of the same material as the thermocouple.  

What are skin temperature thermocouples ?

Description : What are skin temperature thermocouples ? 

Last Answer : Skin thermocouples are those which are directly connected to the process without any thermowell. Used for measuring the skin temperature of heaters furnaces, flue gas etc.  

What type of sensing element would you use to measure very low temperature ?

Description : What type of sensing element would you use to measure very low temperature ?

Last Answer : The sensing element used for measuring very low temperature is R. T. D. ( Resistance Temperature Detector )

How will you calibrate a temp. recorder using a potentiometer ?

Description : How will you calibrate a temp. recorder using a potentiometer ?

Last Answer : Connect the potentiometer output to the input of temp. recorder. 1. Connect the ( +ve ) to the ( +ve ) and ( -ve ) to the ( -ve ). 2. If ambient compensation is provided ... ambient temp. millvolts to the corr. input millvolts measured. Find out from the chart for the corresponding temperature. 

Why are Thermowells used ?

Description : Why are Thermowells used ?

Last Answer : In numerous application it is neither desirable nor practical to expose a temperature sensor directly to a process material. Wells are therefore used to protect against damage corrosion, erosion, abrasion and high pressure processes. A ... 3. Monel. 4. Alloy steal. 5. Hastelloy 'C'.

Why is a converter used in a temp. recorder ?

Description : Why is a converter used in a temp. recorder ? 

Last Answer : The converter is designed to convert D. C. input voltage into an A. C. input voltage proportional in amplitude to the input.  

What is burnout feature ? Explain.

Description : What is burnout feature ? Explain.

Last Answer : Burnout provides the warning feature of driving indicator the end of scale if the input circuit should open. A burnout resistor is provided which develops a voltage drop between the measuring circuit and the ... Upscale burnout : R value 10 M Downscale burnout : R value 2.2 M 

What is the constant voltage unit ?

Description : What is the constant voltage unit ?

Last Answer : The constant voltage circuit consists of a rectifier, CR, a filter capacitor C1, followed by two stages of zener regulation. Abridge configuration is provided to 1amp line voltage regulation ... , Thus variations. Resisters R2 and R3 form a bridge that any remoment line voltage effects. 

Draw a potentiometer temp. Measuring circuits and explain its?

Description : Draw a potentiometer temp. Measuring circuits and explain its?  

Last Answer : OPERATION : The input to the instrument is a measurement of some in the processes using a sensing element ( such as thermocouple ) or a device to produce direct voltage, which is the voltage (signal) ... to zero results ( null point ) the balancing ( servo motor is be longer driven )   

What is two wire and three wire R.T.D. system ?

Description : What is two wire and three wire R.T.D. system ?  

Last Answer : Two wire R .T .D. system : Two wire RTD system use for short distance like a compressor field local panel. Three wire System : Three wire system use for long distance coke a field to control Run. The third wire is used for compensation of lead wire resistance. 

What is Pt 100 mean. ?

Description : What is Pt 100 mean. ? 

Last Answer : Pt100 means 100 OHMS at 0'C for a platinum resistance bulb.  

Explain the working of an Enraf level gauge?

Description : Explain the working of an Enraf level gauge?

Last Answer : The Enraf precise level gauge are based on servo powered null-balance technique. A displacer serves as a continuous level sensing element. Principle: A displacer with a relative density higher than ... to a remote indicator of which the receiver motor drives a counter indicating level variation.  

How will you check zero of a level D.P. transmitter while is line ?

Description : How will you check zero of a level D.P. transmitter while is line ? 

Last Answer : ١. Close both the isolation valves. ٢. Open the vent valve on L.P. leg and H.P. leg drain. ٣. Check and adjust zero if necessary. 

How will you commission D.P. transmitter in field in pressurized vessel.

Description : How will you commission D.P. transmitter in field in pressurized vessel.

Last Answer : ١. Close both the isolation valves, Vent the H.P. side. ٢. Fill it with the sealing liquid. ٣. Open the L.P. side vent valve. ٤. Adjust zero with suppression spring. ٥. Close the L.P. side vent valve. ٦. Open both the isolation valves.  

What are the limitations of leveltrol ?

Description : What are the limitations of leveltrol ?

Last Answer : The limitations of a level control that it cannot be used for lengths more than 72 inches.  

What is the used of Suppression and elevation ?

Description : What is the used of Suppression and elevation ?  

Last Answer : Suppression and elevation are used on Level applications where (1) transmitters are not mounted on some level (2) Wet leg. i.e. condensable vapors are present.