GENERAL MANUFACTURING GUIDELINES FOR PLC (LEVEL-1 AUTOMATION) SUBMITTED BY SASHIKUMAR G BHARAT HEAVY ELECTRICALS LIMITED INDUSTRIAL SYSTEMS GROUP Prof. C. N. R. Rao Circle I. I. Sc. POST Malleswaram Bangalore 560 012. Industrial Systems Group, Bangalore Page 1/7
TABLE OF CONTENTS SECTION DESCRIPTION OF CONTENT PAGE NO SECTION I SITE DATA 3 SECTION II APPLICABLE STANDARDS 4 SECTION III INSPECTION & TESTING 5 SECTION IV CONTRUCTION GUIDELINES 6-7 Industrial Systems Group, Bangalore Page 2/7
SECTION I SITE DATA 1 Location ---- 2 Altitude above sea level ---- 3 Charging Aisle and Converter Area 50 to 55 0 C (Indoor) 4 Scrap Aisle / General Shop Floor Area 45 0 C (Indoor) 5 Hot Metal / Liquid Steel Handling Area 55 0 C (Indoor) 6 Under direct incidence of sunrays 50 0 C (Indoor) 7 Electrical Room 32±2 0 C : RH 70% (Air-Conditioned) 8 Control Rooms 25±2 0 C : RH 55% (Air-Conditioned) 9 Cable Tunnels 45 0 C (Ventilated) 10 Relative Humidity ---- The ambient environment as mentioned above shall be maintained in the respective rooms for long and reliable service life of the electrical equipment. Note: The electrical rooms, control rooms will be provided with adequate airconditioning system, all automation equipment shall be designed for an ambient temperature of 45 0 C. In addition to this, for the switchboards, the in-panel temperature as per the enclosure used shall also be considered for derating. 1 System Voltage 415V, 3-phase, 4-wire 2 Frequency 50 Hz 3 Voltage Fluctuation ±6% for 415V 4 Frequency Fluctuation ±3% for all voltage levels 5 Fault Level 50kA for 1 sec for 415V 6 System Grounding Solidly earthed for 415V 7 Voltage level of AC-outlets inside rooms 15A, SPN receptacles 240 V AC 8 Control Voltage of automation equipments 240 V AC Industrial Systems Group, Bangalore Page 3/7
SECTION II APPLICABLE STANDARDS The PLC equipment, its accessories and its application shall correspond with the following standards and regulations. 1 NEMA National Electrical Manufacturers Association 2 DIN German Institute for Standardization 3 IEC International Electrotechnical Commission 4 IEEE Institute of Electrical and Electronics Engineers 5 ISA Instrument Society of America 6 ISO International Organization for Standardization 7 IS Indian Standards 8 IPSS Interplant Steel Standards General Specifications for standards: The equipment and accessories shall be in accordance with the latest relevant standards and codes of practice established by the Bureau of Indian Standards (BIS) wherever available, in order that specific aspects under Indian conditions are taken care of. In case where Indian Standards are not available, the equipments and accessories shall conform to the latest standards and codes of practice published by any other recognized National Standards Institutions or latest publications of International Electro-technical Commission (IEC). All electrical equipment shall also conform to the latest Indian Electricity Rules as regards safety, earthing and other essential provisions specified therein for installation and operation of electrical plants. All equipments shall comply with the statutory requirements of the Government of India and the Respective State where the equipment will be installed.. Industrial Systems Group, Bangalore Page 4/7
SECTION III INSPECTION & TESTING The Enclosures shall be inspected for complete integrity with respect to the approved dimension drawings. Tests shall be carried out to ensure correct integrated function as a whole. Test/Warranty Certificates for all brought out items and parts used (along with their serial numbers) are to be submitted and verified. Painting certificate for applicable color and type of coating shall be submitted and verified. Routine test certificates as per manufacturer s procedures shall be submitted and verified. Industrial Systems Group, Bangalore Page 5/7
SECTION IV CONSTRUCTION GUIDELINES 4.1 Mechanical Regulations The Programmable Logic Controllers (PLC) shall be of rugged, modular construction and plug-in-type. The PLC shall be suitable for reliable, failsafe operation in arduous steel plant environment where electromagnetic noise, high temperature, dust, humidity and mechanical shocks / vibrations are prevalent. All Cabinets are of floor standing Type Enclosures and shall be fabricated from CRCA sheet steel of thickness not less than 2mm with welded/modular construction throughout. Side panels, Top & Bottom Cover shall be of 1.6mm thick steel sheet and all load bearing members inside shall not be less than 2mm thickness. Panels shall be of Rittal Make with standard dimension 2000H x 1200W x 800D(excluding plinth). Marshalling panel of 600W shall be considered additionally wherever required. All welds shall be ground smooth and free from weld spatters. All cabinets to conform IEC 297 and DIN 41494 Standards. The front and rear doors (where applicable) shall be with lockable handle (3 levers) and shall open outwards through concealed hinges and shall have 90-120 degree opening range. Four nos Removable eye bolt lifting lugs shall be furnished for each enclosure. The glass in front door (where applicable) shall be of wide toughened timed glass of 4mm thick with rubber beading all around and clamps at back support. Cable access will be from bottom through removable gland plate of 3mm thickness. Painting shall be of RAL 7035 and powder coated. The enclosure should provide full protection from dirt, dust, moisture and other contaminants and will be of IP-42 Grade. Foundation frame shall be made using MS Channel of 100x50x6 mm and will be painted with RAL 7022. 15mm Thick anti-vibration pad between panel and base is to be provided for all enclosures. Suitable stiffeners shall be provided for all Front / Rear Doors. All cubicles, racks and modules shall be provided with readily visible identification labels. All Cubicles shall be provided with two nos Cooling fan on top and louvers with filters on front/back doors. Industrial Systems Group, Bangalore Page 6/7
4.2 Electrical Regulations All wiring inside panels (both Internal & External) shall run through PVC channels with covers. Cable ducts shall have minimum depth of 75mm. PVC wiring channels shall have flammability certification as per UL94V0. PLC I/O Power supplies shall be connected to electrical earth (E1) by minimum 2.5 Sq mm cable. All PLC racks shall be isolated from the body of the Cubicle and connected to Electronic Earth (E2). All Instrument cable screens, etc shall be connected to Instrument/Electronic Earth (E2) All MCBs shall be of D-Curve Characteristic. All Interposing relays (24V DC) shall be of series CS8 with 2No+2NC and of AC15-3A rating. E1 and E2 Earth (30x6mm Cu) are isolated and 16Sq mm cable shall be used for connecting to PLC earth pits. All Power terminals shall be suitably covered with Acrylic sheet. All Internal wiring inside PLC shall be carried out with 1100V Grade multi stranded Copper wires with PVC Insulation. Terminal blocks shall be properly arranged to facilitate easy termination of cables and shall have required clearance to cable gland plates/adjacent terminal rows/panel sides & other installed equipments..color Code: S.NO DESCRIPTION CABLE COLOR CABLE SIZE TB COLOR TB SIZE 1 230V AC PHASE ( UPS - PT1 TO P1 ) RED 6 Sq mm RED 6 Sq mm 2 230V AC NEUTRAL ( UPS - PT1 TO N1) BLACK 6 Sq mm BLACK 6 Sq mm 3 230V AC PHASE ( NON UPS - PT2 TO P2 ) RED 6 Sq mm RED 6 Sq mm 4 230V AC NEUTRAL ( NON UPS - PT2 TO N2 ) BLACK 6 Sq mm BLACK 6 Sq mm 5 230V AC PHASE ( NON UPS - UTILITY ) RED 2.5 Sq mm CONNECTED TO 6 230V AC NEUTRAL ( NON UPS - UTILITY ) BLACK 2.5 Sq mm P2&N2 BUS BAR 7 230V AC PHASE ( UPS -AFTER BUS BAR ) RED 4 Sq mm RED 6 Sq mm 8 230V AC NEUTRAL ( UPS -AFTER BUS BAR ) BLACK 4 Sq mm BLACK 6 Sq mm 9 230V AC PHASE ( NON UPS-AFTER BUS BAR ) RED 4 Sq mm RED 6 Sq mm 10 230V AC NEUTRAL ( NON UPS-AFTER BUS BAR ) BLACK 4 Sq mm BLACK 6 Sq mm 11 ELECTRONIC EARTH GREEN 2.5 Sq mm CONNECTED TO E1&E2 12 POWER EARTH YELLOW/GREEN 2.5 Sq mm BUS BAR 13 DIGITAL INPUT SIGNAL YELLOW 0.75 Sq mm GREY 2.5 Sq mm 14 DIGITAL OUTPUT SIGNAL BLUE 0.75 Sq mm GREY 2.5 Sq mm 15 ANALOG INPUT SIGNAL RED-SCREEN 0.5 Sq mm GREY 2.5 Sq mm 16 ANALOG OUTPUT SIGNAL ORANGE-SCREEN 0.5 Sq mm GREY 2.5 Sq mm 17 RTD INPUT SIGNAL BROWN 0.5 Sq mm GREY 2.5 Sq mm 18 24V DC POSITIVE - UP TO BUS BAR ( BB1 ) BLUE 6 Sq mm BLUE 6 Sq mm 19 24V DC NEGATIVE - UP TO BUS BAR ( BB2 ) WHITE 6 Sq mm BLACK 6 Sq mm 20 24V DC POSITIVE - AFTER BUS BAR BLUE 1 Sq mm BLUE 2.5 Sq mm 21 24V DC NEGATIVE - AFTER BUS BAR WHITE 1 Sq mm BLACK 2.5 Sq mm 22 CONTACT WIRING GREY 1.5 Sq mm GREY 2.5 Sq mm Industrial Systems Group, Bangalore Page 7/7