Section 13 — Electrical

Electrical Standards for Packaged Equipment

IPE Engineering Practice IPE-EP-13-13-1

Document number: IPE-EP-13-13-1 · Section: 13 — Electrical

SCOPE

This Practice governs, as a minimum, the design, fabrication and testing of electrical portions of packaged equipment and process skid mounted electrical equipment.
Any deviation to this Practice must be approved by the procedures described in EP 1–1–3.
A revision bar indicates all changes made to this Revision.

REFERENCES

All applicable sections of the latest standards and codes listed below are a part of this Practice. This includes compliance to the referenced standards and codes within the below listed standards and codes.

STANDARDS AND PUBLICATIONS

STANDARDS AND PUBLICATIONS (CONT.)

IPE Engineering Practices (Continued)
EP 13–14–1 Motor Connection Drawings EP 13–15–1 Equipment Grounding Details EP 13–16–1 Electrical Equipment Shelters EP 13–17–1 Uninterruptible Power Supply EP 13–19–1 Low Volt Automatic Transfer Switches EP 13–21–1 High Voltage Oil, Vacuum, and SF6 Outdoor Circuit Breakers 13.8 KV and Above EP 13–22–1 Actuators for Motor Operated Valves EP 13–24–1 Electrical Bus Duct 480 Volt and Higher EP 13–25–1 Medium Voltage Metal Enclosed Switches (ME Switches)
API Publications
RP 500 Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class 1, Division 1 and Division 2
NFPA
70 National Electric Code 497A Classification of Class I Hazardous Locations for Electrical Installations in Chemical Plants 497 Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas

Although only specific codes and standards are identified in this Practice, this does not relieve compliance to paragraph 2.1 of this Practice.

DEFINITIONS

Contractor – Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.
Inspector – A Inflection Point Engineering, LLC appointed engineer or inspector.
Manufacturer – The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a Manufacturer by a Contractor or the Owner. An indirect order is one issued to a Manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.
Owner – Inflection Point Engineering, LLC .
Owner’s Engineer – A Inflection Point Engineering, LLC appointed engineer.
Purchaser – The party placing a direct purchase order. The Purchaser is the Owner’s designated representative.

SERVICE CONDITIONS

Packaged equipment, unless specified otherwise, shall be designed to operate in a petro– chemical environment, without derating, with ambient temperatures at a 104ºF maximum, – 15ºF minimum at an altitude of 3,300 feet or lower. The Data Sheet shall identify any special conditions known to exist at the applicable location.

DESIGN, CONSTRUCTION AND MATERIALS

Area Classification
The existing area classification shall be as stated in the Data Sheet, EP 13–13–1DS. If the area classification is not given, the package/skid manufacturer/fabricator shall contact the Owner’s Engineer to establish the designated existing area classification of the installation area. The packaged/skid equipment Manufacturer shall provide area classification drawings for their design/layout. The proposed area classification drawings shall be approved by the Owner’s Engineer prior to approval of the electrical system design, procurement of electrical equipment, and fabrication.
Area classification shall be done following the guidelines of API 500, NFPA 497 series, NFPA 70, and EP 13–2–1.
All electrical equipment, materials and fabrication within classified locations shall fully comply with article 500 of NFPA 70, and the contract documents.
Equipment
All electrical equipment shall be from vendors identified on the current (approved) Owner’s electrical/instrument vendors list, unless specified otherwise by the Owner.
All electrical equipment supplied shall be in complete compliance with its associated IPE

Engineering Practice and completed Data Sheet.

Local motor starters shall not be provided, unless specified otherwise by the Owner. Combination motor starters shall be supplied by the Owner. The packaged equipment fabricator shall provide the starting/stopping characteristics of the equipment.
In general, all local controls (start–stop stations, control select stations (H–O–A) etc.) shall be located at the motor/driven equipment. When a packaged unit contains sufficient numbers of motors/electrical devices in a small area (e.g., pump row, fin fan coolers), a control panel may be furnished by the packaged unit fabricator. The control panel, controls and wiring shall comply with EP 13–2–1 and this Practice. The enclosure and devices shall be suitable for the environment and classification of the installed location.
Miscellaneous electrical devices (switches, pushbuttons, relays, receptacles, lighting fixtures etc.) to be furnished shall be as approved by the Owner to ensure uniformity of materials and devices at the plant installation site.
All equipment shall be furnished assembled to the extent practicable, and for easy field assembly where shop assembly is not practicable. All hardware/materials required shall be furnished with complete instructions for field assembly. The Manufacturer/fabricator shall itemize unassembled equipment in the bid.
Motors

NEMA Frame Motors
Motors 1/2 to and including 200 HP shall be NEMA frame motors in full compliance with this Practice and EP 13–3–4. The motor Manufacture shall be as approved by the Owner.
Each motor shall be specified via an Owner approved Data Sheet, EP 13–3–1DS and/or EP 13–3–4DS.
Large Frame Medium Voltage Motors
Motors larger than 200 HP shall be medium voltage motors in full compliance with EP 13– 3–2. The motor Manufacture shall be approved by the Owner.
Each motor shall be specified via an Owner approved Data Sheet, EP 13–3–2 DS.
Control Panels
Instrument panels shall comply with the requirements of EP 12–1–1.
Electrical equipment control panels shall comply with this Practice and applicable sections of EP 13–2–1 and EP 12–1–1 for materials and fabrication.
All control panel layouts and material lists shall be approved by the Owner prior to fabrication.
Wiring
Instrument wire/cable: Instrument wire/cable shall comply with EP 13–2–1 paragraph 6.4, and EP 12–1–1.
Electrical power and control wire: Electrical power and control wire/cable shall comply with EP 13–2–1 for type and wiring methods (this shall include EP 13–8–1 and EP 13–8–2 and completed Data Sheets).
All alarm wiring shall be stranded copper, single conductor or multi conductor, 14 AWG minimum size, 600 volt type XHHW, XHHW–2 insulation (THHN/THWN is suitable for jacketed multi conductor cable). DC instrument alarm circuits shall comply with EP 13–2–1 paragraph 6.4 and EP 13–2–1. In addition to the above alarm wiring shall comply with EP 13–8–1 and its associated completed Data Sheet. NOTE: Low voltage power/control (600 volt) insulation shall be rated 600 volts to ground.
Wiring System
Wiring systems are classified into three major groups as follows:
Medium voltage (4160V and below)
Low voltage (600V and below)
Instrumentation (low–level)
Care shall be taken not to induce voltages in low–level signal wiring and electronic instruments. Compliance with EP 13–2–1 shall govern required spacing between power and instrumentation wiring, unless relief is granted by the Owner.
All wiring shall be run in threaded hot dipped galvanized steel conduit with NPT threaded malleable iron fittings.
Conduit systems shall comply fully with this Practice and EP 13–2–1.

The packaged/skid equipment manufacturer (fabricator) shall provide NEMA 4X stainless steel junction boxes with terminal strips for incoming/outgoing wiring requiring connection by the Owner. Each terminal shall be uniquely and clearly identified as to item number and destination. Provide a separate terminal for each connection to be made by the Owner or for connections between common wires including instrument wire shields. Duplicate terminal designators can be used where there are connections between common wires.
Terminations on low voltage power and power control circuits shall be made by using insulated barrel compression spade or ring lugs. Instrument wiring terminations shall be as specified in EP 13–2–1 paragraph 6.4.
Wiring shall be routed to minimize accidental mechanical abuse and possible damage from fire or overheating.
Electrical terminal strips shall be of the open type with insulating barriers between adjacent terminals. Terminals shall be rated 600V. A minimum of 10 percent spare terminals shall be provided. Each terminal shall be clearly identified with consecutive numbers.
Separate junction boxes shall be provided for each type of wiring; i.e. power, alarm and instrument interconnections.
Junction boxes shall be as follows:
NEMA 4X Stainless Steel Gasketed - Non–Classified Area
NEMA 4X/7 - Class I Div. 2 Area (where required)
The following shall be grouped in separate junction box(es).
Thermocouples and RTDs.
Analog signals (4–20 ma DC).
Contacts for alarms, relays and solenoids using dc voltage.
120–VAC signals and 120–VAC power.
Separate conduit systems shall be provided for different types of wiring as outlined in EP 13–2– 1.
Wiring shall run from terminal to terminal with no splices or twist–on wire connectors.
Terminations of thermocouple extension wire shall be directly to the instrument terminals or to junction box terminals. Terminal connections shall be made directly to the terminals without the use of lugs or other connections. The shield of a single pair thermocouple extension wire shall be grounded at the thermocouple head only, except where individual thermocouple wiring is collected at the local junction box. The shields for the individual pairs shall be connected to the overall shield for the multiple cable and grounded at the local junction box.
Instrumentation wiring shall be twisted pair shielded with an overall shield as specified in EP 12–1–1 and EP 13–2–1.
Instrumentation installation and separation shall be as specified in EP 13–2–1. Deviations must be approved by the Owner.

Each wire shall be tagged at both ends by means of a plastic type sleeve marker. Wire marks shall be in accordance with the Owner approved tagging method and wiring diagrams. Tape type wire markers are not acceptable.
All conduit seal dams shall be placed by the packaged equipment/skid supplier. SEALS SHALL ONLY BE POURED WHEN APPROVED BY THE OWNER’S ENGINEER. For the case of field pouring of seals the packaged equipment supplier shall provide all materials required for sealing. Seals poured prior to field installation shall be identified by painting the seal with red paint.
The minimum above ground conduit size allowed shall be 3/4 inch.
Nameplates
Plastic lamicoid nameplates, when supplied, shall be white with black letters. The minimum letter size shall be 3/8 inch. Safety/warning nameplates shall be plastic lamicoid tags with bold white letters on a red background. Nameplates shall be fastened with corrosion resistant stainless steel screws or reusable plastic rivets.
All nameplates shall be approved by the Owner.
Each junction box or terminal box shall have a permanent plastic nameplate numbered per approved for construction drawings.
All instruments furnished shall be identified with permanently attached non–corrosive stainless steel nameplates.
All pushbutton stations, lights, handswitches, instrument indicating meters, horns, bells, etc. shall be clearly identified with plastic lamicod nameplates as indicated in paragraph 5.7.1.
Terminal blocks and other internally mounted devices within control panels and junction boxes shall be uniquely identified with plastic nameplates. The nameplates shall be secured to the device mounting plates/back panels with stainless steel screws.
Space Heaters
Outdoor control panels, when specified on the Data Sheet, shall be provided with thermostatically controlled anti-condensation heaters. Heaters and thermostats shall be installed for easy removal and replacement. Space heaters shall be wired for 120 volts, 1–phase operation.
Other heaters shall be as follows:
Up to 1,800 watts, 120 volts, 1 phase
1,801 to 3,000 watts, 208 volts, 1 phase
Above 3,000 watts, 480 volts, 3 phase
Surface temperature of heaters shall not exceed 160ºC. Care must be taken to insure that the surface temperature and thermostat complies with the classification and group in which it is operating.

TESTING

Inspection and testing of electrical equipment portions of packaged equipment shall be done in accordance with the individual equipment EP testing requirement, with EP 13–2–2 when the equipment is in the field, and the contract documents.

All electrical power and control wiring shall be checked for insulation resistance with a 500 volt DC insulation tester.
All circuits shall be checked for continuity and compliance to the wiring diagrams.
A complete functional test shall be performed. The Owner’s external devices can be simulated with temporary switches, relays, lights, etc. to aid in exercising each circuit/loop to demonstrate proper operation of all devices. A function/operational test shall be performed for all electrical equipment at rated voltage. The packaged equipment Manufacturer/fabricator shall be responsible to perform the functional testing including running of contract motors. The fabricator shall provide power and motor starting equipment. The fabricator shall assume responsibility for any damage to equipment during testing.
Test data required during functional testing shall be as agreed to by the Owner during the pre– award contract meetings.
When a witness test is specified, the test shall be witnessed by the Owner.
When component witness test is specified, as part of the equipment EP, its content shall be as approved by the Owner and shall be witnessed by the Owner.

DRAWING AND DATA REQUIREMENTS

All drawings, test reports, and manuals shall be provided in the quantities and format indicated on the Data Sheet. When electronic format is specified, refer to EP 2-5-2.

Information to be Supplied with Quotation
Specific listing of any exceptions to the specified requirements. If no exceptions are taken, this shall be so stated.
Indicate all equipment or features included but not necessarily specified.
Drawings/sketches showing:
Equipment layout/orientation with dimensions
Preliminary mounting details
Provide a complete detailed list of electrical loads on/in the package, including the nature of the load, e.g. voltage, horsepower.
The Manufacturer shall separately list the horsepower, speed and voltage for all motors proposed in the quotation.
Provide an itemized list of all items that are not in compliance with UL and/or not UL listed.
Cost for witness testing.
Itemize list of unassembled electrical equipment/material.
Information to be Submitted to IPE for Approval After Receipt of Order
Typical drawings are not acceptable unless revised to show as–built/supplied equipment and identify the specific equipment ordered.
Provide complete layout drawings to show electrical equipment locations to include elevations, junction box locations, control stations, and Owner’s interconnection/tie–in points.

Panel elevations and layouts.
Elementary diagrams
Elementary/schematic diagrams shall be furnished for all electrical/instrument systems furnished.
Each electrical elementary/schematic shall show all control devices and device contacts, each of which shall be labeled with its proper ANSI device function number.
Detailed wiring diagrams showing:
All wiring within each panel/skid etc.
Identification of all terminal blocks.
Separate drawings for each junction box.
All interconnection wiring between units and between the package/skid and the Owner’s wiring.
Clear identification by some distinguishing method of all wiring which is to be installed by the Owner.
Area classification drawings for the package/skid being supplied. This drawing shall comply with the requirements detailed in EP 13–2–1 and the requirements of Section 5.1 of this Practice.
Detailed listing of all nameplates.
The information requested in paragraphs 7.2.2 through 7.2.7 shall be issued to the Owner’s Engineer and Owner for review and approval prior to start of fabrication.
Certified Information to be Supplied
All information requested in paragraphs 7.1, 7.2 and 7.3 “as built”.
Individual test reports and drawings for electrical equipment supplied per the applicable electrical equipment Practice.
Test reports for testing as detailed in paragraph 6.0, the Data Sheets for all equipment supplied and other requirements of the purchase documents.
Installation, operation and maintenance manuals shall be provided for the electrical/instrumentation equipment furnished. Provide in the quantities shown on the Data Sheets.
Provide all fabrication drawings as outlined in EP 13–2–1.
Spare parts listing.

SPARE PARTS

A complete spare parts recommendation, with pricing, based on the total purchase order is required within 60 days after the Manufacturer receives the purchase order. Spare parts recommendations shall include:

A complete spare parts list, including parts location diagrams and/or drawings.
List of spare parts as recommended by the Manufacturer to be on hand during plant start– up and the first year’s operation.

SHIPPING

‘Preparation for Shipment’ shall be in accordance with the Manufacturer’s standard, unless otherwise noted on the ‘Request for Quotation’ and/or Purchase Order. The Manufacturer shall be solely responsible for the adequacy of the ‘Preparation for Shipment’ provisions employed in respect of materials and application, to provide materials and application, to provide materials to their destination in ex–works condition when handled by commercial carrier systems.
Special consideration shall include:
Ensure that all electrical connections are tight and that circuits are isolated.
Electrical/instrumentation equipment that may be subject to damage in transit, shall be removed, tagged and separately packaged to avoid damage.

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Disclaimer. This material is provided for informational and educational purposes only and does not constitute professional engineering advice. Calculations, reference data, and methodologies are based on published standards and accepted engineering practice but are not a substitute for engineering judgment, site-specific analysis, or review by a licensed Professional Engineer. Inflection Point Engineering, LLC makes no warranties, express or implied, regarding the accuracy, completeness, or fitness for a particular purpose of any content presented here, and shall not be liable for any direct, indirect, incidental, or consequential damages arising from its use. Users assume all risk associated with applying this content to real-world design, operations, or decisions.