Section 13 — Electrical

Motor Connection Drawings

IPE Engineering Practice IPE-EP-13-14-1

Document number: IPE-EP-13-14-1 · Section: 13 — Electrical

SCOPE

• This Practice along with Engineering Practices, provides the recommended design practices for installation of motors, sizes 1/2 to 200 horsepower.
• This Practice shall be applicable to both new facilities and the modernization of existing facilities.
• Any deviation to this Practice shall be in accordance with the procedure given in EP 1–1–3.
• A revision bar indicates all changes made to Revision.

REFERENCES

• The latest edition of the following standards and publications are referred to herein.

STANDARDS & PUBLICATIONS

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 Refining Company 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.
• Megger – Shall be used to identify a resistance measurement meter (instrument).
• Owner – Refining Company.
• Owner’s Engineer – A Refining Company appointed engineer.
• Purchaser – The party placing a direct purchase order. The Purchaser is the Owner’s designated representative.

GENERAL DETAILS

• Conduit and Wire Sizes

Conduit and wire sizes shall be sized and installed per this Practice, EP 13–2–1 and NFPA 70. Where conflicts between the Owner EP’s and NFPA 70 occur, the more conservative method shall have precedence. It should be noted that wire sizes may increase because of design requirements (voltage drop) and conduit and seal fitting requirements may require an increase in size to accommodate changes in wire size and type of insulation.

• Classified Areas

The installation of equipment in classified areas shall be in compliance with NFPA 70.

• Materials

The materials identified, Figures 1 through Figure 4, are preferred. Suitable substitutes that are both equivalent and interchangeable may be supplied if approved by the Owner.

• Installation

The National Electric Code NEC, (NFPA 70), EP 13–2–1 and EP 13–15–1 shall be the basis for motor connections and grounding. Where there is a conflict between the NEC and other references, the more conservative method shall have precedence.

• Tray Installation

Figures 4 through 17 are for installations when cable tray and MC type cable is specified by the Owner.

• Grounding
• Motor frame, power/control conduit and control station grounding shall be per EP 13–15–1 and EP 13–2–1.
• Motor frame grounding for tray installations shall be per EP 13–15–1 with the grounding conductor from either the below grade ground system ground pad, or from a ground wire routed in the overhead tray, where overhead tray ground wire shall be connected to the load source ground.
• All motors shall have a ground wire with the power wiring. Wire size shall be per the current NEC based on the phase conductor wire size required. Appropriate Burndy crimp–type lug shall be used for the ground wire and termination provided in the motor terminal box.
• All flexible conduit shall be watertight, UL listed, with ground and connected using UL listed grounding connectors. External copper ground wire across flexible conduit shall only be used when required per the NEC. The ground wire with the phase conductor shall be the NEC ground for motor circuits.

5.0 FIGURES

FIGURE 1

1/2 THRU 60 HP MOTOR CONNECTION (SEE FIGURES 1A THRU 1C FOR ITEM DESCRIPTION)

NOTES:

• Provide conduit seal only when approved by Owner.
• For motor and control station support grounding, see EP 13–15–1, Figure 5.
• All conduit system shall not interfere with removal of the motor end bell or fan shield.
• Installation shown is for Class1, Division 2, Groups C and D only.
• Motor termination type/method to be as approved by Owner (eg. tape, heat, shrink, etc.)
• NEC sized grounding conductor required for flex conduit larger than 1–1/4 inch diameter.

FIGURE 1A

1/2 THRU 20 HP MOTOR CONNECTION (ITEM DESCRIPTIONS FOR FIGURE 1)

FIGURE 1B

25 THRU 40 HP MOTOR CONNECTION (ITEM DESCRIPTIONS FOR FIGURE 1)

FIGURE 1C

50 THRU 60 HP MOTOR CONNECTION (ITEM DESCRIPTIONS FOR FIGURE 1)

FIGURE 2

75 THRU 200HP MOTOR CONNECTIONS

(SEE FIGURES 2A AND 2B FOR ITEM DESCRIPTIONS)

NOTES:

• Provide conduit seal only when approved by Owner.
• Installation shown is for Class1, Division 2, Groups C and D only.
• Motor frame, power conduit, control conduit, control station to be grounded to made earth ground system, see EP 13–15–1, Figure 5.
• Motor termination type/method to be as approved by Owner (eg. tape, heat, shrink, etc.) Conduit systems shall not interfere with removal of the motor end bell or fan shield.

FIGURE 2A

75 THRU 125 HP MOTOR CONNECTION (ITEM DESCRIPTIONS FOR FIGURE 2)

FIGURE 2B

150 THRU 200 HP MOTOR CONNECTION (ITEM DESCRIPTIONS FOR FIGURE 2)

NOTE: All sizes shown are in inches, unless otherwise noted.

FIGURE 3

15, 20 AND 25 HP FIN FAN MOTOR CONNECTION

NOTES:

• All conduit systems shall not interfere with removal of the motor end bell and rotor.
• Installations shown are for Class 1, Group C and D, Division 2 only.
• The motor connection must comply with the area classification of the Installation site.

FIGURE 4

CL 1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 0 - 5 HP FEED OVHD. IN TRAY

FIGURE 5

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 7 1/2 - 10 HP FEED OVHD. IN TRAY

FIGURE 6

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 15 HP FEED OVHD. IN TRAY

FIGURE 7

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 20 HP FEED OVHD. IN TRAY

FIGURE 8

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 25 HP FEED OVHD. IN TRAY

FIGURE 9

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 30– 50 HP FEED OVHD. IN TRAY

FIGURE 10

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 60 HP FEED OVHD. IN TRAY

FIGURE 11

CL1, DIV.2 0 NON–HAZ. AREA HORIZONTAL MOTOR 75 HP FEED OVHD. IN TRAY

FIGURE 12

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 100 HP FEED OVHD. IN TRAY

FIGURE 13

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 125 - 150 HP FEED OVHD. IN TRAY

FIGURE 14

CL1, DIV.2 OR NON–HAZ. AREA HORIZONTAL MOTOR 200 HP FEED OVHD. IN TRAY

FIGURE 15

VERTICAL CABLE CHANNEL END SUPPORT AT CONTROL STATION (LOOKING DOWN ON TOP)

FIGURE 16

CABLE CHANNEL BOLTED TO CABLE TRAY FOR SUPPORT

FIGURE 17

CABLE CHANNEL BOLTED TO UNISTRUT FOR SUPPORT

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