By measuring the electrical properties such as capacitance and Tan-Delta regularly on periodical basis, it is possible to ensure the operational unexpected breakdown. Dissipation factor (Tan Delta) is one of the most powerful off-line nondestructive diagnostic tool to monitor the condition of solid insulation of various high voltage equipment.
Capacitance and Tan Delta values obtained on new insulation are treated as benchmark readings. Then by measuring and comparing the periodical readings of the capacitance and Tan-Delta of the insulating material with the benchmark readings, one can know the rate of deterioration of the health of the insulation.
Electrical properties of the insulating system change due to age and continuous electrical street. The principal contributor to the unexpected breakdown of the high voltage equipment is the insulation failure. As compared to the magnetic, conducting & insulating materials which form the basics of any electrical equipment, the insulating material is more prone to service stresses like thermal stress, electrical stress, mechanicals stress, environment stress etc.

WHEN TO CHECK CAPACITANCE & TAN-DELTA

• During manufacturing process preferably at each stage.
• In service & will be depend on rate of change of Tan-Delta Vs Voltage Vs Time (Month / Year).
• Frequency of testing depends on history of past failures on same machine.
• Frequency of testing depends on environmental conditions. More humidity, temperature, pollution would require frequency measurement of Tan-Delta.

KNOWING THE RATE OF DETERIORATION, WE CAN BE ABLE TO

• Predict the future unexpected breakdown of the insulation of HV equipment.
• Plan the maintenance schedule.
• Repair the insulation before actual flashover, saving high cost of replacement of material which will reduce the inventory well as delay in procurement at the last minute.
• After repair, quality of insulation can be checked before returning the equipment to service.

THIS SYSTEM INCLUDES FOLLOWING ITEMS

• High Voltage Source
• Tan Delta Bridge
• Output Testing Leads.
• The system can be designed, manufactured and supplied according application and requirement of the customer.

Features :

• 4.5 Digits LED display
• Range : 0 TO 1999.9 µW to 199.99mW.
• High Measurement Current : 100A DC max.
• True Four wire resistance measuring technique eliminates lead resistance errors inherent in 2 wire systems.
• Fully protected against overloads.
• Proven design

TECHNICAL SPECIFICATIONS: MODEL:CRM 100-1Display : 4 ½ digits, digital LED displayResistance Range : 0 - 1999.9µΩ -19.999mW - 199.99mΩSelectable by a range selector switchTest current switch : 0 - 100 A DC maxProtection : Electronic type short circuit & overload protection on output.Meter provided :a) 4.5 digit, digita resistance meter.b) 3.5 digit, digital ammeter.b) 3.5 digit, digital DC mV meter.Power : 230V AC, 50 HzType of measurement : 4 Wire Measurement System

System Consist Of Following Instruments : Oil Dissipation Factor Meter (Model-ODF) This instrument measures dissipation factor (Tan-Delta) of the insulating liquids (oil) with the help of IR Tester and three terminal oil cell with heating chamber.

Features :

• Push button controls for rapid testing.
• Fully protected against all overload and short-circuits.
• Drift free operation.
• Guard terminal and built-in EARTH.
• Push button self indicating controls for charge, measure & discharge operations.
• Maximum output current is made limited to safe value to eliminate the risk of serious shocks.
• Suitable for testing resistivity of the insulating liquids when used with oil cell as per IS.

FEATURES :

• Potential-free start and stop signal.
• Continuously adjustable output, AC A mp. and AC volts.
• Auto cut-off and output isolated.
• Portable model
• Self sensing of contacts, i. e. NO / NC
• Digital ammeter and voltmeter.
• Timer automatically puts OFF the output, when timer reaches to its maximum value of the selected range to ensure safety of the instrument as well as the item under test.
• Wide range of measurement, i. e. from I millisecond. to 9999 secs.

APPLICATION:The protective devices such as relays, overload coils, circuit breakers must be checked regularly to ensure that, they are always ready to operate correctly. If a fault occurs in the equipment, which they are protecting, routine relay testing will quickly detect the faulty, incorrectly adjusted protection circuit and will possibly prevent serious damage to plant or injury to personnel. Apart from checking the protective circuits correctly, it is usually necessary to measure its operating time. The micro controller based time interval meter is used for this purpose in all AJIT brand relay tester.

Features :

• Safety interlock on high voltage test chamber & zero start.
• The sets are available with printer &/or RS 232 interface.
• Equipment to enable easy, accurate & safe measurements.
• Micro controller controlled, saves operator's time.
• Recall of individual tests including breakdown voltages, averages & the test number, all displayed digitally.
• Emergency exit allows the operator to quit the process.

Applications :Theses tester sets are used for determining the di-electric BDV of insulating oils, both new and in-service from transformers, switchgear and other electrical equipments.

Safety Arrangement :

• Zero start interlock.
• Oil chamber door interlock
• Low level, high level interlock for motor
• Fast acting electronics type current sensing circuit in the event of insulation failure of the oil under test
• Facility to quit the process any time.
• Printer : Built in thermal printer

Stabdard Accessories :

• Mains cord, detachable, 1.5 mtr long.
• Oil test cell with electrodes
• Electrode spacing gauges GO & NO-GO
• Operating instruction manual.

This instrument is capable of producing 3 Phase AC Voltage with phase shifting arrangement between the phases simultaneously.Voltage OutputRange : 415V ph-phPhase Shift : settable by selector switchesPhase angle setting : A rotary switch will be provided toselect the phase angle in Lead or Lag in steps of 15 Degree.Protection : Glass fuses in the input supply and output.Power Supply : Three Phase, 415V AC 50 Hz, 120 degree apartCabinet : Powder Coated sheet metal cabinet.

By measuring the electrical properties such as capacitance and Tan-Delta regularly on periodical basis, it is possible to ensure the operational unexpected breakdown. Dissipation factor (Tan Delta) is one of the most powerful off-line nondestructive diagnostic tool to monitor the condition of solid insulation of various high voltage equipment.
Capacitance and Tan Delta values obtained on new insulation are treated as benchmark readings. Then by measuring and comparing the periodical readings of the capacitance and Tan-Delta of the insulating material with the benchmark readings, one can know the rate of deterioration of the health of the insulation.
Electrical properties of the insulating system change due to age and continuous electrical street. The principal contributor to the unexpected breakdown of the high voltage equipment is the insulation failure. As compared to the magnetic, conducting & insulating materials which form the basics of any electrical equipment, the insulating material is more prone to service stresses like thermal stress, electrical stress, mechanicals stress, environment stress etc.

WHEN TO CHECK CAPACITANCE & TAN-DELTA

• During manufacturing process preferably at each stage.
• In service & will be depend on rate of change of Tan-Delta Vs Voltage Vs Time (Month / Year).
• Frequency of testing depends on history of past failures on same machine.
• Frequency of testing depends on environmental conditions. More humidity, temperature, pollution would require frequency measurement of Tan-Delta.

KNOWING THE RATE OF DETERIORATION, WE CAN BE ABLE TO

• Predict the future unexpected breakdown of the insulation of HV equipment.
• Plan the maintenance schedule.
• Repair the insulation before actual flashover, saving high cost of replacement of material which will reduce the inventory well as delay in procurement at the last minute.
• After repair, quality of insulation can be checked before returning the equipment to service.

THIS SYSTEM INCLUDES FOLLOWING ITEMS

• High Voltage Source
• Tan Delta Bridge
• Output Testing Leads.
• The system can be designed, manufactured and supplied according application and requirement of the customer.

Features :

• 4.5 Digits LED display
• Range : 0 TO 1999.9 µW to 199.99mW.
• High Measurement Current : 100A DC max.
• True Four wire resistance measuring technique eliminates lead resistance errors inherent in 2 wire systems.
• Fully protected against overloads.
• Proven design

TECHNICAL SPECIFICATIONS: MODEL:CRM 100-1Display : 4 ½ digits, digital LED displayResistance Range : 0 - 1999.9µΩ -19.999mW - 199.99mΩSelectable by a range selector switchTest current switch : 0 - 100 A DC maxProtection : Electronic type short circuit & overload protection on output.Meter provided :a) 4.5 digit, digita resistance meter.b) 3.5 digit, digital ammeter.b) 3.5 digit, digital DC mV meter.Power : 230V AC, 50 HzType of measurement : 4 Wire Measurement System

System Consist Of Following Instruments : Oil Dissipation Factor Meter (Model-ODF) This instrument measures dissipation factor (Tan-Delta) of the insulating liquids (oil) with the help of IR Tester and three terminal oil cell with heating chamber.

Features :

• Push button controls for rapid testing.
• Fully protected against all overload and short-circuits.
• Drift free operation.
• Guard terminal and built-in EARTH.
• Push button self indicating controls for charge, measure & discharge operations.
• Maximum output current is made limited to safe value to eliminate the risk of serious shocks.
• Suitable for testing resistivity of the insulating liquids when used with oil cell as per IS.

FEATURES :

• Potential-free start and stop signal.
• Continuously adjustable output, AC A mp. and AC volts.
• Auto cut-off and output isolated.
• Portable model
• Self sensing of contacts, i. e. NO / NC
• Digital ammeter and voltmeter.
• Timer automatically puts OFF the output, when timer reaches to its maximum value of the selected range to ensure safety of the instrument as well as the item under test.
• Wide range of measurement, i. e. from I millisecond. to 9999 secs.

APPLICATION:The protective devices such as relays, overload coils, circuit breakers must be checked regularly to ensure that, they are always ready to operate correctly. If a fault occurs in the equipment, which they are protecting, routine relay testing will quickly detect the faulty, incorrectly adjusted protection circuit and will possibly prevent serious damage to plant or injury to personnel. Apart from checking the protective circuits correctly, it is usually necessary to measure its operating time. The micro controller based time interval meter is used for this purpose in all AJIT brand relay tester.

Features :

• Safety interlock on high voltage test chamber & zero start.
• The sets are available with printer &/or RS 232 interface.
• Equipment to enable easy, accurate & safe measurements.
• Micro controller controlled, saves operator's time.
• Recall of individual tests including breakdown voltages, averages & the test number, all displayed digitally.
• Emergency exit allows the operator to quit the process.

Applications :Theses tester sets are used for determining the di-electric BDV of insulating oils, both new and in-service from transformers, switchgear and other electrical equipments.

Safety Arrangement :

• Zero start interlock.
• Oil chamber door interlock
• Low level, high level interlock for motor
• Fast acting electronics type current sensing circuit in the event of insulation failure of the oil under test
• Facility to quit the process any time.
• Printer : Built in thermal printer

Stabdard Accessories :

• Mains cord, detachable, 1.5 mtr long.
• Oil test cell with electrodes
• Electrode spacing gauges GO & NO-GO
• Operating instruction manual.

This instrument is capable of producing 3 Phase AC Voltage with phase shifting arrangement between the phases simultaneously.Voltage OutputRange : 415V ph-phPhase Shift : settable by selector switchesPhase angle setting : A rotary switch will be provided toselect the phase angle in Lead or Lag in steps of 15 Degree.Protection : Glass fuses in the input supply and output.Power Supply : Three Phase, 415V AC 50 Hz, 120 degree apartCabinet : Powder Coated sheet metal cabinet.