SECTION 13325
CONTROL PANEL ENCLOSURE CONSTRUCTION
PART 1 GENERAL
1.1 DESCRIPTION
A. This specification applies to construction of all panels shown on P&IDs, Network Diagrams, construction drawings and described in the specifications. This includes the Process Communication Panels PCPs, Local Control Panels LCPs, RTUs, and all other electrical enclosures shown on the P&ID and other drawings.
B. This specification covers the technical requirements for the fabrication, engineering, wiring and installation for instrumentation, control and electrical enclosures as described in the Specifications and as shown on the Drawings.
C. Panels provided under this section shall meet the requirements of UL-508. All panels shall bear the UL-508 serialized label or be third party certified when delivered to the job site. All field modifications shall be in conformance with UL-508. When the Owner accepts the panels, the contractor shall certify that the panels have retained their UL labeling or third party certification.
D. All wiring shall be in complete conformance with the National Electric Code, state, local and NEMA electrical standards. All incoming and outgoing wires shall be connected to numbered terminal blocks and all wiring neatly tied and fastened to chassis as required.
E. Each control panel with a Ethernet Switch, PLC, operator interface, or other ethernet device within enclosure shall have an industrial type exterior mounted Ethernet Receptical programming port with the enclosure NEMA rating same as the control panels.
1.2 SUBMITTALS
A. Submittals shall be as specified in the following specification sections:
1. Division 1
2. Section 13320 General Instrumentation and Control
PART 2 PRODUCTS
2.1 GENERAL
A. Indoor enclosures shall be NEMA 12 when located in electrical rooms. Indoor enclosure shall be NEMA 4x stainless steel when not located in electrical rooms.
B. All conduit entry into the enclosures shall be sealed with non-hardening sealing compound.
C. Condensation protection shall be provided. Enclosure shall have a heater which operates continuously to prevent condensation build-up. Exception to this requirement may be given if panel is in an electrical room with heating and air conditioning.
D. All equipment in enclosures shall operate from single 120 Vac power supply circuit. (If panel contains motor controls, panel shall have a single supply at the voltage of the motor controls. Provide control transformer as necessary to provide control panel with 120Vac control voltage.)
E. Acceptable enclosure manufacturers:
1. Hoffman Engineering Company
2. Or approved equal
F. Acceptable heater manufacturers:
1. Hoffman Engineering Company
2. Or approved equal
G. Acceptable heat exchanger manufacturers:
1. Hoffman Engineering Company
2. Noren Products Incorporated
3. Or approved equal
2.2 PANEL CONSTRUCTION
A. Enclosures
1. NEMA 12 enclosures shall be fabricated from 12 gauge cold rolled sheet steel or better.
2. NEMA 4x enclosure shall be fabricated from 10 gauge 304 stainless steel with continuous SS hinges.
3. Stiffening members shall be provided for strength and stiffness as required.
4. Seamless welded construction shall be used throughout. All exposed seams shall be continuously welded and ground smooth.
5. Lifting rings shall be provided for panels in excess of 100 pounds.
6. Double doors shall be of the flush type construction with continuous hinge and gasketing.
7. Doors shall be equipped with two (wall mounted) or three (floor mounted) point latching mechanism.
8. A hasp and staple shall be provided for padlocking.
9. Subpanels shall be provided, and mounting shall be designed for easy removal.
10. A print pocket shall be attached to the inside of each door.
11. Panels to be sized to accommodate a minimum of 25% additional I/O of each type. This is in addition to 25% spare I/O provided per PLC specification.
2.3 PANEL GROUNDING
A. Each enclosure shall be provided with an isolated ground connection or buss, which shall be tied to the facilities, building, or installations grounding system, through a #6 AWG insulated grounding conductor, only at the final connection to the ground rods.
2.4 PANEL WIRING
A. Wiring within the enclosure shall be continuous and shall be terminated only at terminal blocks or equipment terminals.
B. Not more than two wires shall be terminated at any terminal block.
C. Wiring splices and wire nuts will not be permitted within the enclosure.
D. Wiring within the enclosure shall be protected as follows:
1. In general, all wiring within the enclosure shall be put in panduit, panduit type G- wide slot wiring duct with matching cover. Panduit shall be white. Maximum fill of Panduit shall be 50%.
2. Wiring outside of the ducts shall be restrained by means of plastic ties.
3. Wiring passing a door hinge shall be grouped and wrapped in a protective wire harness.
4. Provide abrasion protections for any wire bundles passing through holes or across sheet metal edges.
E. In general, wiring within the enclosures shall be as follows:
1. Control wiring within the enclosure shall be #16 AWG stranded.
2. Wiring for long distance DC signals shall be #16 AWG stranded.
3. Wiring for 4-20 mA DC analog signals shall be #18 AWG twisted shielded pair.
4. Wiring for RTDs shall be #18 AWG twisted shielded triad (3 wire RTD) or quad (4 wire RTD).
5. Wiring for thermocouples shall be connected directly to the I/O at the point of the cold junction.
6. Multi-conductor control cables and shielded pair cables between control equipment, control panels and motor starters shall be rated for 600 Volts.
F. Wiring within the enclosure shall follow the following color convention:
1. Neutral conductor shall be white.
2. Hot or phase conductor shall be black for 120Vac and black and red for 240Vac.
3. Grounding conductor shall be green.
4. AC control wiring shall be red.
5. DC (+) power conductor shall blue.
6. DC (-) power conductor shall be blue.
7. DC control wiring shall be blue
8. Current Loop wiring shall be twisted shielded pair cables.
G. AC and DC wiring shall be separated from each other. Where AC and DC wire runs parallel, the minimum separation between them shall be 4 inches. Where AC and DC wire runs across, they shall cross at 90 degree intersections. Provide separate panduit for AC and DC wiring.
H. Equipment and signal ground wiring, as well as Neutral wiring shall not be daisy- chained. They shall each be terminated at isolated, bused terminal blocks.
I. Each conductor end shall be terminated at a terminal block or at an equipment wiring terminal. Each terminal block shall have a unique identification number. The terminal
blocks shall be arranged and numbered in consecutive order, based on standard alphanumeric order.
J. Terminal blocks within each enclosure shall be grouped as follows:
1. 120 Volts AC power
2. 120 Volts AC control wiring terminal blocks
3. AC isolated Neutral Busbar terminations
4. 24 Volts DC power terminations
5. 24 Volts DC control wiring terminal blocks for discrete signals
6. 24 Volts DC Common Busbar terminations
7. Analog signal wiring terminal blocks (for 4 - 20 mA DC signals)
8. RTDs
9. Thermocouples terminations
10. Isolated Grounding Busbar terminations
K. Provide 25% spare terminal blocks, (minimum of 6), for each type used in each enclosure.
2.5 TERMINAL BLOCKS
A. Terminal blocks within enclosures shall be of the high density modular types, constructed of nylon material, suitable for mounting on standard DIN rails. Termination type shall be tubular screw with serrated pressure plate.
B. Terminal blocks which require jumpers shall be provided with center jumper option and utilize center jumpers.
C. All current carrying parts (metal bodies) shall be made of nickel/tin-plated copper.
D. Ground terminals shall be color coded in accordance with international standard, which shall be yellow/green.
E. Panel power distribution and digital output terminal blocks shall be fused lever disconnect type with illuminated blown fuse indication.
F. The terminal block system shall be as manufactured by Allen-Bradley or Phoenix.
2.6 PANEL POWER DISTRIBUTION REQUIREMENTS
A. Panels shall always be designed to have one power supply source. If supply voltage is higher than 120Vac a control transformer with 100% spare capacity shall be supplied.
B. One GFI Service outlet shall be supplied inside each panel.
C. Panels with Uninterruptible Power Supply (UPS) shall be designed such that if the UPS system fails a contactor at the output of the UPS shall transfer the panels UPS powered loads back to the panels Utility power supply. Panel shall provide a “UPS Fail” contact closure alarm prewired to a terminal strip for connection to the SCADA system or other alarm system.
2.7 PANEL ACCESSORIES
A. Each enclosure shall be provided with internal panel LED or fluorescent lights, which shall be provided with and actuated through a door light switch. The lights shall turn on automatically when the enclosure door is opened and turn off automatically when the enclosure door is closed. The panel lights shall be strategically placed to provide maximum possible illumination coverage of the panel/enclosure interior.
B. The enclosure vendor shall be responsible for all interposing relays which may be necessary to interface all field equipment or Motor Control Centers, to provide a complete functional system.
C. The enclosure vendor shall be responsible for all intrinsic safety relays and panel construction methods which are necessary to interface with field equipment and instruments that are mounted in explosion hazard areas. See NEC for requirements.
D. The enclosure vendor shall be responsible for all analog signal boosters and isolators which may be necessary to interface all field instrumentation equipment or Motor Control Centers, to provide a complete functional system.
E. Current to current isolators shall be furnished and installed as required, to eliminate interface and ground loop problems. Inputs shall be 4 - 20 mA DC. Outputs shall be 4 - 20 mA DC isolated, into at least 800 Ohms. Power to the isolators shall be 115 Volts AC, 60 Hertz.
F. The enclosure vendor shall be responsible for providing and sizing all instrument loop power supplies. The enclosure vendor shall be responsible for providing and sizing all PLC and Operator Interface Power Supplies. The power supplies shall be sized to include at least 100% spare capacity. Where PLC manufacturer and Operator Interface Manufacturer’s recommend separate power supplies for isolation or other reasons separate power supplies shall be provided.
G. PLC, Operator Interfaces and each type of I/O shall have separate fusing or breakers as required by manufacturer instruction manuals or as necessary to eliminate electrical ground loops or electrical/communication noise.
H. Provide communication port optical isolation as necessary for Ethernet and serial ports to ensure proper communications between networked devices.
I. Panels with PLCs and/or operator interface terminals shall have front of panel mounted RJ-45 Ethernet Port connection receptacle for use by programmer. Port shall be connected to panels internal network switch via internal CAT 5 cable jumper.
2.8 EQUIPMENT IDENTIFICATION AND WIRE TAGGING
A. All panel wiring shall be identified by means of heat shrink or label machine printed type wire markers. Tagging shall correlate to loop naming.
B. All communications cabling shall be identified by means of heat shrink type or label machine printed wire markers.
C. Each component mounted within the enclosure shall be provided with equipment identification. Equipment and device nameplates or identification shall be of engraved laminated plastic, black lettering on white background or similar professional looking identification.
PART 3 EXECUTION
A. NOT USED
END OF SECTION
No comments:
Post a Comment