CABLES PHOTO

PVC CABLES

XLPE CABLE

MICC CABLE

ARMOURED CABLE

PAPER INSULATED CABLE

LEAD COVERED CABLE

UPS

UPS

The circuit drawn pertains to a regular industrial UPS (Uninterruptible Power Supply), which shows how the batteries take control during an outage in electrical supply or variation beyond the normal limits of the voltage line, without disruption on the operation providing a steady regulated output (5 Volts by LM7805) and an unregulated supply (12 Volts).
The input to the primary winding of the transformer (TR1) is 240V. The secondary winding can be raised up to 15 Volts if the value is at least 12 Volts running 2 amp. The fuse (FS1) acts as a mini circuit breaker for protection against short circuits, or a defective battery cell in fact. The presence of electricity will cause the LED 1 to light. The light of LED will set off upon power outage and the UPS battery will take over
The circuit was designed to offer more flexible pattern wherein it can be customized by using different regulators and batteries to produce regulated and unregulated voltages. Utilizing two 12 Volt batteries in series and a positive input 7815 regulator, can control a 15V supply.
Industrial UPS are generally categorized as:
Standby – battery backup and surge protection
Line Interactive – variable-voltage transformer and regulates the input AC voltage
Online – supplies all or at least a part of the output power

DOL STARTER FOR FAN MOTOR

DOL STARTER POWER AND CONTROL DIAGRAM

DOL STARTER POWER AND CONTROL DIAGRAM

3300 / 440V TRANSFORMER MAINTENANCE PROCEDURE

HTCB – VCB (TOSHIBA MAKE)                        LTCB – ACB (TOSHIBA MAKE)

1.      Obtain work permit from operations for the required transformer with proper tag number.

2.      Check all the parameters on both HV/LV side and both LV & HV are closed. Check both transformers are in service.

3.      Prepare caution notice/permit to work and display it on HV & LV panels.

4.      Switch off LV side breaker (ACB), and then switch off HV side breaker (ACB) of current tag number. Make sure that there is no power interruption.

5.      Open the HT breaker panel. Lift the latch pin upward on both the handles pull the breaker outward from service position to test position.

6.      Switch off control supply and remove control plugs and the front o ‘CB’. Remove the stopper plate, pull the  VCB outside breaker compartment

7.      Open LV (ACB) breaker panel.

8.      Lift the flapper (Middle of breaker – right hand side) upward and insert rack out/in handle into the slot.

9.      Rotate the handle anti-clockwise till it reaches disconnected position. Pull the ACB outward after lifting the stopper levers on both sides of ACB

10.  Position the trolley carrier and move it inside, below the lifting pins or both sides of ACB. Lift the trolley upward will it carries breaker. Pull the trolley outside and place the breaker on floor.

11.  Release charged spring by manually operating on/off of VCB and ACB.

12.  Put the earthing hand le of 3.3 KV side earthing switch compartment which is above VCB cubicle.

13.  Slide the stopper plate towards right hand side, lift earthing leaver and release the stopper plate.

14.  Remove the castle key from ACB, insert in the earthing breaker operate the key to release the locking pin.

15.  Insert the rack-in handle to the slot (right side) and turn it clockwise if it reaches service position.

16.  Remove handle and switch on control supply of earthing switch.

17.  Close panel door and turn earthing switch on. Observe earthing indication.\provide barrier caution tape on both sides of transformer of correct tag number.

18.  Clean whole transformer. Open LV & HV side terminal boxes. Inspect and tighten terminations hi-speed bushings.

19.  Clean and tighten all earthing connections.

20.  Measure insulation resistance of primary and secondary windings with earth and between windings. For HT winding use 2.5KV megger. For LV winding use 500V megger. Remove LT side neutral link before meggering.

21.  Close the terminal boxes. Check inert gas pressure. Take transformer oil for testing.

22.  Clean, check and inspect VCB and ACB for looseness and any abnormality. Apply petroleum jelly for finger contacts. Megger insulation resistance values of terminals. Measure contact resistance of poles.

23.  Check manual operations of ACB and VCB.

24.  Insert VCB in breaker compartment up to test position. Put back the stopper flap in position. Make sure breaker is off plug in control pin plugs and switch on control supply.

25.  Rack out earthing breaker to disconnected position on LV side. Take out the castle key.

26.  Insert the ACB using trolley and rack – in by turning rack – in handle clockwise to service position.

27.  Perform functional test by operating protective devices.

28.  Push both breakers to service position. Switch on HT breaker. Observe voltage.

29.  Close LT breaker. Observe voltage and current on both HT & LT sides.

30.  Remove caution tags and cancel permit.

31.  Enter rack – in / rack – out details in substation log book.

32.  Record all readings and values in history cards.

33.  Send oil samples for testing acidity and dielectric strength.

MAINTENANCE PROCEDURE FOR SUBSTATIONS AND SWITCHGEAR

MAINTENANCE PROCEDURE FOR SUBSTATIONS AND SWITCHGEAR

GENERAL

             

The maintenance of the switchgear and electrical equipment can be carried out safely and efficiently through the following steps.

1.      Understanding the job

2.      Availing the permit to work

3.      Organizing for the work

4.      Availing the shut-down

5.      Maintenance work

6.      Closing the work

7.      Normalizing power status

8.      Returning the permit

9.      Record results.

1.)               Understanding the job:

a)      The Supervisory staff must have a clear idea about the job to be carried out in detail and stepwise. They should have a fair idea of this job to their subordinates.

 SUBSTATIONS RM01 TO RM13 MIANTENANCE OF 11 K. V./ 3.3K.V. TRANSFORMER

After obtaining the work permit, check the tag number on the VCB Panel.

Request M-20 staff to trip and earth 11K.V. connected feeder with copy of the work permit.

M-20 staff will place earthing truck in place of drawn out 11KV breaker.

Confirm that M20 staff makes this earthing truck “ON” and then lock it using your own lock and carry the key with you.

While going back to your substation confirm that the transformer under maintenance has no humming noise.

Check again the YCB panel; it should be in off position. This confirms the operational status of the inter-trip with M-20 feeder.

Rack-out the YCB

Open the cubicles, holds both handle and lift the latch and with sufficient force, draw-out the breaker and the breaker can be drawn-out to its Test/Rack-out position. At the correct position, the latch shall come back down to its position.

Switch off the control supply and disconnect the control cable plugs. Remove stopper strip in front of the VCB by unscrewing the nuts. Pressing two knobs to their handle hooks, draw-out breaker completely out of panel.

Earth the cable side of the incomer.

Insert the earthing handle in its position, push the latch and operate.

Identification of the job includes knowing location of the equipment, its function along with its general characteristics such as voltage level, capacity, duty etc.

Alternate arrangement should be considered and must be provided for continuity of power supply before starting to avail shut down on the equipment.

Availing Permit to Work

Permit to work must be availed.

1.1.1.  By a person competent to receive it.

1.1.2.  From a person competent to issue it.

1.1.3.  For a valid assigned and approved work.

1.1.4.  After having explained to Operation staff details of steps of the work to be done.

1.1.5.  With due intimation and signature of the KNPC.

Engineer in case the work involves switching operation of any UPS system.

            In case the work involves probability of annunciation / alarm to any department other than operation, i.e. Fire Station then such department should be informed accordingly about the work prior to taking up such work.

Permit to work must be readily available / displayed at the site of work to the inspecting authorities.

Organizing the work

Caution Notice duly filled in and signed must be prominently displayed at the equipment control panel under work and half portion of Caution Notice should be displayed at the equipment.

Staff for the maintenance work should be nominated and informed accordingly.

Equipment for work must be identified by at least two senior supervisor staff for its correctness before starting any work.

Cordon-off the correct equipment with caution tape around.

Inter-relation between the equipment under maintenance and that related to it by Power-flow or process logic must be clearly understood by the person authorized to work. In case of any doubt, seniors must be consulted till satisfactory clarification.

Availing shut-down

Check the prevailing status of the Power-flow before starting any work, its total load in case of parallel Operations of the Transformers and the status of the Bus-tie.

Just before availing shut down, inform Operations staff (and Fire Station if required) about your steps of operation and theirs expected alarms and changes in Power – flow.

Switch – off the circuit Breaker after confirming the tag number, this operation should be done by the authorized person who avail the work permit and in the presence of the area engineer.

Rack-out the circuit Breaker.

Earth the circuit as per manufacturer procedure and using the proper tools.

MAINTENANCE WORK

Allocate the job to certain staff whom should be only allowed to be present at he site.

Carry out the required maintenance for the equipment as per the CMMS and the manufacturer recommendations.

Closing Down Maintenance Work.

Remove cordon-tape around the equipment (if applicable).

Clean the site.

Declare to your staff that the work is completed.

Normalizing the system.

Remove the circuit earthing as per the approved procedure after checking he tag number.

Rack – in the circuit breaker as per the approved procedure.

Returning permit to work.

Inform Operation staff that the work is completed.

Operate the earthing handle downward using sufficient force. The earthing switch will operate making the incoming cable earthed.

Observe and check correctness of indications i.e. VCB OFF condition Earth Switch ON condition.

Lock the cubical compartment.

Maintenance of the transformer.

Allocate this job to certain staff whom will be only allowed to enter the transformer yard.

Clean externally the body of transformer starting from the top downwards, watching for any damage, oil leakage etc.

Open up primary and secondary side cable box covers. Open also the neutral C.T. Box cover and clean them all.

Check for any spark – pitting or looseness of connections and if so, rectify.

Check and clean all earthing connections and refit them.

Check the condition of the silica gel and, if necessary, replace it along with necessary oil quantity.

Clean and check the control panel for the cooling system of the transformer for manual operation of the fans.

Megger the transformer as under:

1.      Making earthing truck at M-20 S/S “OFF”.

2.      Switch “OFF” the 3.3KV side earthing switch.

3.      Megger 11 KV to transformer body and note down results.

4.      Measure insulation resistance values’ of primary and secondary

5.      Sign in column no.9 for having completed the work. See that all copies have this signature.

6.      Confirm that operators signature is obtained on all three copies for having agreed that the work has been completed.

7.      Take away your copy of the permit to work.

Recording the results

1.     Record the job done in the substation log book

2.     Make entries in the history card file about the maintenance work done and sign it.

For primary to earth and primary to secondary use 5KV megger.

For secondary to earth use 2.5KV megger.

Close the terminal boxes and ensure no tools, materials left inside.

Take transformer oil (testing of dielectric strength and acidity) samples.

Position the lifting trolley of potential transformer near the P.T. cubicle. Lift the latching pin on P.T. handle on both sides, pull out outward. Lock it in trolley. Remove control plug pins. Pull out and place it on floor.

Position the same trolley near lightning arrestor cubicle. Lift the locking pins on L.A. handles, pull outward. Lock it in trolley and pull out.

Clean P.T & L.A., tighten connection, and check for abnormality. Measure insulation resistance values (2.5 KV megger).

Rack – in P.T. & L.A. following same procedure.

Clean VCB, lubricate all moving parts, and check for manual operation, clearance of contacts. Measure contact resistance and insulation values of poles.

Insert VCB in test position. Replace stopper flap in its original position. Connect control plug pins to VCB and switch on control supply.

Carry out functional tests.

a)      Inter trip

b)     Buchholzs relay trip alarm

c)      Winding temperature and oil level alarms.

Closing down maintenance work.

1.      Remove cordoning-off tape around the transformer.

2.      Confirm that transformer yard has danger warning signs in their proper place.

3.      Clean the transformer yard.

4.      Ask everybody to go out of transformer yard and lock the yard from outside.

5.      Calibrate the measuring and protecting instruments with KNPC approval and record results.

6.      Declare orally to all that the work is completed.

Normalizing the system

1.      Return the key and open lock of earthing truck in M-20 S/S.

2.      Request M-20 S/S staff to remove earthing truck and insert 11 KV VCB in service position.

3.      Request M – 20 staff to make concerned 11 KV feeders VCB ON.

4.      Check the humming noise of this transformer is audible.

5.      Checks from the panel that correct values o voltage are available.

6.      Close 3.3KV breaker of the transformer.

7.      Check the load shared by this transformer with previous values and that of the other transformer.

Returning permit to work

Inform operation staff that the work is completed.

Sign in column no.9 for having completed the work. See that all 3 copies have this signature.

Confirm that operator’s signature is obtained on all three copies for having agreed that the work has been completed.

Take away your copy of the permit to work.

Recording the Results

Make entries in the history card file about the maintenance work done, sign it.

Obtain oil sample results and study them. Also enter this result in the history file.

OIL FIELD CABLES

Q. What are the different sizes of the cables?

A. 0.75, 1.5, 2.5, 4, 6, 10, 16, 25, 35, 50, 70, 95, 10, 150, 185, 240, 300, 400, 600,  (Dimensions are in Square mm).

Q. What is the use of cable gland?

A.  Cable glands are used to protect against mechanical damages o cables during entering in junction box, MCC etc. it also give earth continuity of cable Armor and equipment body.

Q. What type of Cable gland used in Oil Field?

A.  In explosion proof areas double compression glands are used to avoid the gasses entering in the electrical apparatus.

Q. What are the Cables used in Oil Field?

A.         PVC – Poly Vinyl Chloride

            

            XLPE – Cross Linked Poly Ethylene

             

            LC – Lead Covered

           

            SWA – Steel Wire Armoured

            

            PILC – Paper Insulated Lead Covered

           

            MICC – Mineral Insulated Copper Conductor

Q. What is MICC? Where it is used? What mineral used in this cable?

A. Mineral Insulated Copper Conductor and it is used for fire alarm systems and Lightings systems at Hazardous area without using conduits and Magnesium oxide is used as mineral.

Q. What types of Cable joint and termination kits used?

A. Cold Compound joint kits. Hot Compound joint kits and Heat Shrinkable joint kits,

Hot Compound Termination and Heat Shrinkable Termination kits,

Q. What is ferrule and where is used?

A. Ferrule is used to connect two conductors during jointing. Three types are Crimping Type and Soldering Type for High Voltage Cables as well as for Medium Voltage Cables and for Low voltages ferrules are PVC Insulated.

Q. Why Lead Covered Cables are used in Oil Fields?

A. Lead Covered Cables are used in Oil Fields due to avoid damages of PVC Insulation, by hydrocarbon gases and chemical corrosion.

Q. How many types of lugs are used?

A. Crimping type and Soldering type lugs are used for cable terminations.

Q. How to check the cable fault?

A.  As follows:

·        Isolate the cable

·        Megger the cable

·        Trace the cable fault through cable fault locator and cable route through cable route locator

·        If the cable resistance is high use the burnout test kit

Before cutting the cable use spiking gun for safety

ILLUMINATION

ILLUMINATION: 

The illumination is defined as the luminous flux received per unit area.

Mathematical illumination = Luminous flux / area = lumens/m2

INCADESCENT LAMP: 

The lamps consist of an evacuated glass bulb or gas filled having fine metallic wire within it. The filament material normally used is tungsten. Titanium and Carbon also used for filament. The filament should have the following properties.

1.       Melting point should be high

2.       Vapor pressure and temp coefficient should be low

3.       Material should be ductile and mechanically strong enough to  bear vibration during use

Tungsten filament lamps have an average life of100 hour under normal conditions.

SODIUM VAPOUR LAMP:  

This type of lamp is of low luminosity, so the length of this lamp is large. To get the required length it is made in the form of a ‘U’ tube.  Two oxide coated electrodes are sealed into the ends. The tube contains a little sodium and neon gas. The U tube is enclosed in a double walled vacuum flask to keep the temperature within working range. Before the lamp starts working sodium is in the form of a solid deposited on the side of tube walls. In the beginning it operates as a low pressure neon lamp with pink colour. The lamp gets warm, sodium is vaporized and it radiates yellow light and after about 10-15 minutes, the lamp starts giving full light.