Our range of outdoor oil cooled current transformers has the following specifications:

• To step down line current to a value which is suitable for standard measuring instrument, relays etc.
• To sense abnormalities in current and give current signals to protective relays to isolate the defective system. 11 kV to 33 kV Metering (0.2 to 3.0) Protection (5P - 10P)

Features:

• The transformers are oil filled in M.S. tanks & chambers together with suitable porcelain bushing.
• High quality C.R.G.O. silicon steel is used in the transformer.
• High quality crepe insulating paper is used to build up main insulation.
• Semiconducting shield is used to give linear distribution of electric stress along the length of the bushing.
• Filtered & de-aerated EHV grade oil is filled in current transformers while current transformer is under vacuum.

To seal it, the space left for expression on the top is filled with dry and pure nitrogen through non returnable valve at pre-determined pressure.

Type	Live or Dead tank
Operating Voltage	11kV, 33kV
Operating temperature	-10°C to 40°C
Conforms to	IS - 2705.
11kV, 33kV.	Upto 2500 Amps.
Secondary Current	5a & 1A (Others on Request)
Short time thermal current & its duration	Upto 40kA for 1 second (Others on request)
Rated burden	5, 10, 15, 20, 30VA (Others on request)
Accuracy Class	0.2, 0.5, 1.0, 5P10, 5P15 (Others on request) (For differential protection, REF protection, Bus Bar protection, CT with Accuracy class PS can be offered.)
Frequency	50Hz

Direct measurement of voltage in high voltage system is not possible because of insulation problem in measuring instruments. It is not possible to use voltage through the system directly for protection purpose due to its high value & high insulation problem. In such conditions voltage transformers are used. It has the following features:

• The transformers are oil filled, assembled in M.S. tanks & chambers together with suitable porcelain bushing.
• High quality C.R.G.O. silicon steel is used in the transformer.
• High quality kraft & crepe insulating paper is used to build up main insulation.
• Semiconducting shield is used to give linear distribution of electric stress along the length of the bushing.
• Filtered & de-aerated EHV grade oil is filled in CTs while CT is under vacuum.

To seal it, the space left for expansion on the top is filled with dry and pure nitrogen through non returnable valve at pre determined pressure. Design incorporating stainless steel bellows instead of nitrogen cushioning is also available.

Electrical specifications:
Type	Single pole insulated & double pole insulated.
Operating Voltage	Single pole insulated 11kV, 22kV, 33kV.
	Double pole insulated 11kV, 22kV, 33kV.
11kV, 33kV.	Upto 2500 Amps.
Burden	50VA, 100VA, 150VA, 200VA (Others on request)
Accuracy	0.2, 0.5, 1.0, 3.0, 3P, 6P.
Frequency	50 Hz
Operating temperature	-10°C to 40°C
Frequency	50Hz
System Condition	Earthed, unearthed.
Conforms to	IS3156

H.T. metering cubicals are incorporated with current transformers and potential transformers using resin developed insulating material system, having graded siliceous material and are bonded together with polymer resin system. These moldable materials facilitates integrated design to current carrying and voltage grading components. They can be classified as having:

• Good electrical, mechanical and weathering properties
• Extensively field tested

Novelties:

• Compact in volume and weight
• Fire and explosion proof
• Maintenance free
• Seal less

Features:

• Excellent partial discharge characteristics
• The current and potential transformers are as per the IS standards
• For current transformers as per clause no. 9.1.1 of IS 2705 (Part - I) 1992.
• For potential transformers as per clause no. 9.1.1 of IS 3156 (Part - I) 1992

We offer potential transformers that are used in current carrying and voltage grading equipment. These are good conductors of electricity and are used in numerous industrial applications. These are available in diverse designs and specifications to suit varying requirements.

Input	240V single phase, 50Hz. A.C.
Output	0 - 100KV / 0 - 60KV center top earthed
Capacity	2 / 1KVA. intermittent
Indication	Mains 'ON' and H.T. 'ON' Lamp
Metering	72mm / size back of panel mounting A.C. Voltmeter to monitor output voltage.
Protection	Electronic, fast acting over current tripping device sensing HT Current directly
ISS Reference	IS / 6792 / 1972 latest
Frequency	50Hz

The relay testing equipment is a portable apparatus, which is designed for checking the operating characteristics of protective relays on site. Since a relay in the system is called into action to deal with a fault only in a long while, its failure to operate correctly on that occasion means unavoidable damage to plant or waste of money spent on installation. Periodic field testing is the best way of ensuring the integrity of the protective relays, but the position is complicated because of the fact that the protective relay is solely concerned with fault conditions, and hence it cannot readily be tested under normal operating conditions.

Specifications :
Phase angle regulation

• 0 - 360 deg. with coarse and fine regulation
• 60 deg. in step and in between continuously variable

Instruments

• 1 no digital volt meter, 0 - 300 volts to monitor output test voltage with a facility to inject voltage suddenly. A parallel potential free contact to initiate digital timer.
• 1 no phase angle meter, 0 - 360 deg. range (optional)
• 1 no digital time interval meter, 0 - 1000 sec. with a facility of start / stop the timer with NO/NC potential free contacts. (optional)

Input supply system
415 volts, 3 phase wire, 50 hz
Output I
A.C. voltage source with phase shifting arrangement
Voltage regulations
0 - 200 volts continuously variable at a max. capacity of 20 V
Output II
D.C. Voltage source.
Range
110 volts with / - 20% with fine control
Capacity
250 MA.

Instrument
digital D.C. Voltmeter, 0 200 volts.
Output III
D.C. Current source.
Range
0 - 1000 ma.
Regulation
0 - 1000 ma. continuously variable

The knee point voltage test kit is a portable apparatus which is designed for checking the knee point voltage of protection class current transformers having secondary current ratings of 1 A and 5 A. There is a possibility of occurrence of faults in every day operations of electrical power system. Since protection class current transformer in the system is called into action to deal with a fault once in a long while, its failure to operate correctly on that occasion means avoidable damage to plant or waste of money spent on installation.

Periodic field testing and testing prior to commissioning of the current transformers is the best way of ensuring the integrity of the electrical power system, since it cannot be readily tested under normal operating conditions. Hence this test kit is a must for every substations.

The knee point voltage test kit are voltage injections sets which provide the necessary voltage for both 1 A and 5 A secondary rated protection class current transformers, to check whether their operating characteristics are within the prescribed maximum exciting current limits and do not go into saturation at the prescribed maximum knee point voltage levels of the protection current transformers. A digital current ammeter and voltmeter is provided to record the test values. The test kit is designed to ensure the testing set output without any distortions.

Specifications:

Input voltage
Single phase 230V AC, 50c/s.
Output voltage

• 0 - 60 V @ 5 A.
• 0 - 2000 V @ 1 A.

Output voltage regulation
0 - 100%
Duty cycle
5 minutes "ON" and 5 minutes "OFF".

Oil test set is an equipment designed to test the dielectric strength of insulating oils as per relevant specifications viz. IS 6792. It is a useful equipment for transformer switchgear manufacturing units, oil filtering agencies, repair shops and electrical maintenance.

Safety features:

• Zero inter locking arrangement
• A transparent hood (cover) on the test cup with a door inter locking micro switch.

Special features:
Resin encapsulated H.T. transformer
Construction:
In a naturally air cooled, portable sheet metal casing (60 KV) models
Optional:
Motorised version, to uniform increase the output test voltage between 0 - 60KV / 0 - 100KV @ 2KV / Sec. Approx.

Specifications:
Input
240V Single Phase, 50Hz. A.C.
Output
0 - 100KV / 0 - 60KV center top earthed
Capacity
2 / 1KVA. Intermittent
Indication
Mains 'ON' and H.T. 'ON' Lamp
Metering
72mm / size back of panel mounting A.C. Voltmeter to monitor output voltage.
Protection
Electronic, fast acting over current tripping device sensing HT current directly
ISS reference
IS / 6792 / 1972 latest

These are low voltage high current A.C. power supplies, output isolated from input. Output may be single range or multi range involving series parallel connections of secondary windings of loading transformer. The primary current injection sets are useful for testing current operated devices such as relays, current transformers etc. This is an asset for electrical testing laboratories, power houses, sub-stations etc. Portable models can be easily taken to the field for on site testing.

Accessories:
A digital time internal meter with 3.1/2 digit L.E.D. indication in two ranges 0 - 10/100 sec. supply voltage for time internal meter 200 V, 1 phase, Hz A.C.

Electrical specifications:

Input
240 V, 1 phase, 50Hz A.C. or 415 V, 1 phase, 50Hz A.C.
Output
0.1000/2000/3000/4000/6000 AMPS. sleeplessly variable.
Capacity
2/4/6/8/10 KVA.
Indication
Neon lamp
Metering
96 mm2 or 144 mm2 size moving iron type ammeter to monitor output current
Protection
Fuse rewireable / HRC on input lines. MCB in Brush arm of continuously variable voltage auto-transformer.
Addititional facility
240 V 1 Ph. supply with switch, fuse for time internal meter.
Construction
Two piece construction, part I consisting of control and indicating components and part II, consisting of transformer in naturally air-cooled sheet metal casing With covering lid and carrying handles. For laboratory use two sections can be kept side by side on a table.

The meter testing benches are designed to work from 3 phase 50 c/s. having voltage 400 to 440 volts between the phases. The test bench is suitable for testing meters under balanced and unbalanced condition of load against rotating sub-standard meters of 5 Amp 240 volts giving accuracy not worse than 0.5. The loading arrangements is based on phantom load principle separate circuit being provided for supplying current and voltage. The bench is provided with indicating instruments of accuracy not worse than 1.5 to indicate Amp and Volts respectively. It is suitable to test 20 Nos. 3 phase meters at a time.

Specifications:

Current range :
0.5, 1,2.5,10,20,50,100,120 Amps.
Voltage range:

• 3 x 110 / 63.5 Volts.
• 3 x 220 / 127 v & 3 x 440/ 254 Volts.

Requirements :
The test bench is suitable for testing electricity meters of the following ratings :

• 3 phase 4 wire KWH meters
• 240 Volts between phase and neutral current range from 0.5 Amp to 120 Amp.
• 3 phase 3 wire KWH meters
• 415 volts between phase - range 0.5 Amp to 120Amp.
• 3 phase 3 wire KWH meters.
• 110 volts between phase- Range 1 Amp to 5 Amp.
• Single phase two wire KWH meter 240 volts. - between phase, neutral - range 2.5 Amp to 40 Amp.
• 3 phase 3 Wire and 4 wire RKVAH meters - 415 volts and 240 volts., between phase, neutral - range 0.5 Amp to 120 Amp.
• 3 phase 3 wire RKVAH meters - 110 volts between phases - range 1 Amp to 5 Amp.
  

We offer metering cubicals that can be installed electrically in the incoming supply point and in step down transformers at the consumers installation. These comprises of rigid welded structural frame enclosed completely by M.S. angle of minimum size 50x50x5mm. To ensure the safety of the equipment we enclose all the compartments of the cubicle  from inside and with detachable covers and components are bolted. We ensure that the cubicle is compact enough to prevent the ingress of water. All doors and removal covers are gasketed all around with neoprene gaskets and the cubicle meets the requirements of IP-55 protection as per IS-12063, if the air vents are closed.

Electronic lock (optional): A dynamic electronic locking system for the cubical shall be offered as optional item. The dynamic lock consist mainly of:

• Master unit with LCD to programme Remort at purchaser office.
• Portable remort with keyboard to operate the door of the panel lock.
• Panel locl with sensors to lock and unlock doors of the cubical.