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Electrical Condition Survey Procedures and Forms for Buildings

1 ELECTRICAL CONDITION SURVEY FOR BUILDINGS

2 1 How to Conduct an Electrical Condition Survey

2 3 PURPOSE:

1 2 To systematically investigate the condition and adequacy of the electrical power distribution system in any building or structure for compliance with good engineering design practice and National Electrical Code.

4 3 EQUIPMENT REQUIRED:

1 2 NEC National Electrical Code 1999

3 4 Digital Multimeter: Fluke 8060A

5 Clamp-on Current Probe: Fluke I80

6 7 Insulated Screw Driver

8 9 Flash Light

10 Micrometer 0-1

11 12 Outlet Tester Daniel Woodhead 1750 or 1756

13 14 GFI Tester 15 Kohm Resistor in 3-Prong Plug

15 Ground loop impedance tester Ground Check Model 7100 ECOS Electronics Corp.

16 17 Wire Gauge

18 Light Meter GE 213 or attachment for fluke

19 Tape Measure

20 21 Condition Survey Form

22 Blank Panel Directory 1 phase and 3 phase

4 PROCEDURE:

1 2 Start at transformer, KVA size is usually printed on side of transformer. Record this. Obtain impedance for Short Circuit Calculation from power company. (R, X, Z, and Primary Short Circuit KVA if available).

3 4 R = resistance, X = reactance, Z = impedance

5 6 Is metering Utility Company on the side of the building or subfed from Forest Service owned distribution system? Check one.

7 8 Is service drop aerial or underground, size: AWG or MCM, type: copper (CU), or aluminum (AL.), insulation type: RHH, RHW, THW, non. Length of service from transformer to building.

9 10 Is there a main switch or circuit breaker on side of building or on meter distribution pole? If so, size, accessibility good, bad?

11 12 What is system voltage, phase, wire?

13 14 Most common: 120/240 Volt, 1 phase, 3 wire;

15 120/240 Volt, 3 phase, 4 wire, Delta;

16 17 120/208 Volt, 3 phase, 4 wire, Wye;

18 19 277/480 Volt, 3 phase, 4 wire, Wye.

20 21 Wire size: Usually printed on insulation, if not, measure insulation diameter, with micrometer then go to NEC Table 5, page 70-753 of insulation to find wire size under proper insulation type. If circuit is de-energized, actual wire diameter may be measured and wire size found in Table 8 page 70-758, but this is dangerous as power can be turned on, and I would not recommend this method.

22 23 Panelboards: Note manufacturer and catalog number, main breaker size and interrupting rating, main buss rating, (usually printed inside cover), number of circuits.

24 25 Directories: Make as-built panel directory on back of condition survey sheet, and a one line diagram if multiple main disconnects and subpanels are in building.

26 27 Service entrance: Type and size of conductors copper, aluminum, insulation type THW, XLP, RHH, RHW, etc., if printed on wire.

28 29 12. Grounding: Check for ground continuity from panel to water pipe or ground rod and wire size.

30 31 13. Turn off main breaker or switches.

32 33 14. Remove panel front.

34 35 15. Turn on power.

36 5 16. No Load Voltage Measurements:

1 1 Turn all branch circuit breakers or main breaker off for no load voltage measurements. Measure voltages with voltmeter line-to-line, (phase-to-phase) 1 to 2, 2 to 3, 1 to 3 on three phase, 1 to neutral, 2 to neutral for single phase.

2 6 Full Load Voltage Measurements:

1 1 Turn on all branch circuit breakers. Turn on all electrical equipment, (measure amperage on main line to make sure main circuit breaker or fuse won't be tripped).

2 3 Repeat voltage measurements described in 16 above.

2 7 Full Load Current Measurements:

1 2 With all loads on in 17 above measure the current with the clamp on ammeter on the conductor to each phase of the main breaker, Line 1, Line 2, Line 3 for three phase and neutral, and Line 1, Line 2 and neutral for single phase. Measure the current on each branch circuit with all equipment on. AMPS measured should be no greater than 80% of wire ampacity and circuit breaker size except for motor circuits during start-up. Write amperage down beside each circuit on panel directory. Motor circuits only; the running current should be no greater than 80% of wire ampacity. Breaker may be sized anywhere from 125% to 250% of the wire and motor nameplate full-load current.

3 4 Example: 12 gauge wire with 20 Amp breaker, measured load 18 Amp. This circuit is overloaded, load should be 80% of 20A or 16A max.

5 8 Wiring method:

1 2 Nonmetallic sheath cable, EMT, electrical metallic tubing (thin wall), RGC Rigid galvanized conduit, (like water pipe).

3 4 20. Circuits Adequate:

5 6 Check number of spare circuits in panel.

7 9 Lighting:

1 2 Measure level with foot candle meter, replace any missing or burnt out lamps before measuring.

3 10 Receptacles:

1 2 2 wire ungrounded or 3 wire grounded, check with outlet tester for open-ground and reverse polarity. Check with ground loop impedance test if available, maximum 1.25 ohms in ground circuit for 20A circuit. If 2 wire outlets, use 3 to 2 prong cheater, touch ground wire to center screw on outlet to see if box is grounded. If box is grounded replace all 2 wire outlets with 3 wire outlets. Identify broken outlets and those with poor contact for replacement.

3 11 Working Clearance:

1 2 Minimum 36" under 150 volts to ground and 42" over 150 volts to ground in front of panels, any serviceable equipment and control panels; minimum 30 wide; minimum 6-1/4 feet high on new installation after 1978, 30" clearance in front of equipment on existing system.

3 12 Service Drop Transformer to Building

1 2 Conductor undersized (310-16 & 310-17).

3 4 Compound metering, breaker required at each subfeed from main meter.

5 6 Adequate clearance from ground (230-24).

7 8 Transformer undersized, measure current and calculate KVA.

9 10 Conduit too small (Table 3A, Page 70-749).

11 12 Exposed splices or conductors.

13 14 Check aluminum connections, penetrox compound, and lug tightness.

15 16 Check copper also.

17 13 Service Entrance and Panel (weather head to Panel):

1 2 No main disconnect (230-70).

3 4 Main conductors undersized. Check voltage drop at panel no load to full load (310-16 & 310-17).

5 6 Conduit too small. (Table 3A, page 70-749).

7 8 More than 1-6 main disconnects. (230-71).

9 10 Panel overloaded, current greater than 80% of main breaker or fuses.

11 12 Branch circuit breakers overloaded, current greater than 80% of breaker rating. (220-3) measure current.

13 14 Branch circuit conductors too small, measure currents (310-16) also check for voltage drop at load max. 5%, 3%, preferable, no load to full load.

15 16 Breakers hot.

17 18 Check aluminum connections for penetrox, tightness and heat.

19 20 Panel space filled, subpanels added.

21 22 Branch circuits with breakers too large, greater than 125% of load, except motor max. 250% (240).

23 24 Service entrance panel: Neutral and ground must be bonded together, at subpanels neutral must be isolated.

25 26 Ground wire sized properly, ground to cold water pipe (250-94).

27 28 Defective breakers or fuses.

29 30 Panel working area blocked min. 6-1/4" high 30" wide, 3 ft. deep (110-16).

31 14 Branch Clrcuits:

1 2 Exposed Romex not protected, must be stapled to side of studs or above joist or in holes in joists (336).

3 4 Conduits overfilled (Table 3A, page 70-749).

5 6 Loose conduit terminations or joints.

7 8 Junction boxes open, open holes.

9 10 Wrong type of conduit boxes for environment (EMT system in dust filled room or hazardous area).

11 12 Gas-oil houses and paint storage areas not wired explosion proof fixtures, conduit, switches (500).

13 14 Improper splices (open, loose, etc).

15 16 Conductor insulation deteriorated (cracked, frayed).

17 18 Circuits not grounded.

19 15 Outlets, Extenslon and Equipment Cords (Use Outlet Tester):

1 2 Not 3 wire grounded.

3 4 Wired reverse polarity; hot and neutral switched.

5 6 Open ground.

7 8 Bad contacts, plug falls out.

9 10 Broken outlet.

11 12 Cover plate broken or missing.

13 14 Hot and ground reversed.

15 16 Check extension and equipment cords, wires frayed, no bottom cover plate.

17 18 Plug cord grip defective or too small.

19 20 Cord frayed cut or cracked, oil soaked.

21 22 Check GFI outlets with test button or 15 Kohm resistor between hot and ground. GFI should trip at 6 Ma.

23 16 Portable Equipment:

1 2 Check cord for leakage to metal case from hot and neutral with ohm meter, should be in excess or 20 megohms.

3 4 Check ground resistance with ohm meter from ground lug on plug in case should be less than 0.1 ohm.

5 6 Replace any cord on metal case equipment with a 2 wire plug with a 3 wire cord and plug.

7 8 29. Fixed Equipment:

9 10 Check grounding (250).

11 12 Measure current and voltage check against nameplate.

13 14 Disconnects and fuses or circuit breakers properly sized (240).

15

COMPUTER ROOM ELECTRICAL CONDITION SURVEY

1 HOW TO SURVEY A COMPUTER ROOM

1 2 CAUTION: Procedures required by this survey will result in the shut-down of the computer equipment. Make prior arrangements with the computer system operators to schedule a time when computer systems can be de-energized.

3 1 Make a hand drawn sketch of the computer room floor plan showing the locations and types of all computer cabinets, desks, power panels, transformers, uninterruptible power supplies, doorways and windows.

4 1 Fill-in the following data:

5 1 Computer System:

2 1 IBM Model

2 3 Tape Model

4 Other

5 6 B. UPS System:

7 8 Make

9 10 Model

11 12 Smoke Detection for Room: Yes___ No___

13 14 Does computer room have high temperature shutdown thermostat and alarm system if A/C unit fails that shuts off all power?

15 Emergency Power Shut-off at door: Yes___ No___

16 17 If computer room has a UPS system, test UPS operation by manually turning off normal power supply to UPS system. The computer equipment should continue to operate. Yes___ No__

1 If yes, turn normal power back on and proceed to step 4.

2 3 If no, have computer system operator switch off computers, then turn normal power back on. Computer system operator can now restart the computer system. Proceed to step

4 5 If room has an Emergency Power Shut-off at door, have computer system operator push button to shut-off computer equipment.

6 7 Did the computer equipment shut-down? Yes___ No___

8 9 If not, and the system has a UPS, push the emergency power off button on the UPS. The computer equipment should be off now. Yes___ No___

10 11 Have computer system operator switch off computers, reset UPS, reset Emergency Power Shut-off system for the computer room. Computer system operator can now restart the computer system.

7 8 Disconnects required on motors and equipment with motors greater than 1/8 HP and fixed space heaters within sight of equipment.

9 10 Transformers overloaded measure current in each phase and neutral, calculate KVA. Watch out for overloaded neutrals due to harmonics

11 12 NOTES:

13

BUILDING ELECTRICAL CONDITION SURVEY

FOREST_______________________________DATE OF INSPECTION______________

DISTRICT_____________________________

BLDG. TYPE___________________________

FS#__________________ AGE__________

|TRANSFORMER TO BUILDING:____________ |SERVICE: |SUBFEED: |Receptacles: |

|Voltage: 120/240 |Metering: Utility___ |Aerial____ Underground____ |Type 2W not Grounded_____ 3W |

| | | |Grounded_____ |

|WYE______120/208____ |Subfeed___ |Source______________ |# Open Ground_____ # Rev. |

| | | |Polarity_____ |

|DELTA____277/480____ |TRANSFORMERS: |Size____ CU____ AL____ |# Bad Contact_____ # Broken_____|

|Phase 1____ 3____ |Utility______ KVA |Insul Type______________ |Maximum Ground Loop Impedance___ |

|Feeder: Aerial______ |Subfeed______KVA |Length________ | |

|Underground_______ |Grounding: Utility____ |Main Switch: |Lighting: |

|Wire Size_________AWG or MCM |%R____ %X____ %Z____ |Fuse____A CB____A |Indoor: Incandescent_____ |

| | | |Fluorescent_____ |

|Type: CU____ AL___ |Accessibilty:_________ |Weatherproof: Yes___ No___ |Level_____ fc |

|Insul.____________ |Good___ Avg___ Poor___ |Wiring: |Condition_______________ |

| |Lockable Yes___ No____ |NMSC_____ EMT_____ |Outdoor: Incand__ MV___MH_HPS__|

|Service Entrance | |RGC_____ Other__________ |Level? Sufficient_____ |

| | | |Inadequate___ |

|NO LOAD |Primary SCKVA_________ |Grounding: |Subpanels: |

|L1-N______ V_____ |FULL LOAD |Water Pipe_____ Ground Rod__ |Neutral & Ground Bonded |

| | |Other_________ |Together____ |

|L2-N______ V_____ |L1-N______ V_____ |Size___________ OHMS to Ground_____ | |

|L3-N______ V_____ |L2-N______ V_____ |Use 3 point probe tester from RO | |

|L1-L2_____ V_____ |L3-N______ V_____ |Condition____________ | |

|L1-L3_____ V_____ |L1-L2_____ V_____ | | |

|L2-L3_____ V_____ |L1-L3_____ V_____ | | |

| |L2-L3_____ V_____ | | |

| |L1________ A_____ | | |

| |L2________ A_____ | | |

| |L3________ A_____ | | |

| |N_________ A_____ | | |

| | | | |

| | | | |

Transformer impedance & Primary SCKVA, obtain from power company use for short circuit calculations.

Remarks________________________________________________

|SERVICE ENTRANCES AND PANELS: |Circults: | |Panel Overloaded__ |

|PANELS: |Total Panel Spaces_____ |GFI Outlets Needed in Wet Locations & |Defective CB/Fuses_____ |

| | |Tools_____ | |

|Directory: Yes_____ No_____ |Fuses or CB Used_______ |Defective switches, Outlets_______ |>6 Main Disconnects__ |

|Breaker AIC___________________ |Fuses or CB Spare______ |Boxes Open or Holes_________ |Fuses/CB Oversized____ |

|Split Bus_____ |Circuits Adequate? Yes_____ No_____ |Excessive Volt Drop_________ |Aluminum connections bad___|

|Main Bus_____A | |Improper Exposed Splice_____ |Water Damaged Equipment___ |

|Age: Old_____ Med._____ |HAZARDS: |No Lightning Arrestor_______ |Wrong Type of Wire___ |

|Type: Fuse_____ CB_____ |Breakers hot___ |Wrong Type of Boxes_________ |Hazardous Area__ |

|Rating: Main_____A _____A |Other:______ |Corrosion on Equipment______ |Frayed Cords____ |

|Make/Model:________________ | |Conduit Overfilled_ |Defective Tools__ |

|Feeder: Size_____ Insulation_____ |Transformer neutrals overloaded More than |NO Space Left__ |Damaged Insulatlon__ |

| |phase amps_______ | | |

|Conductor: CU_____ AL_____ |Gas-Oil Paint Houses Not Explosion Proof_____|Cords through Walls_________ | |

| |Conductors Undersized/overloaded_____________|36" Panel Front Clearance after | |

| | |1978_______ | |

|Voltage and AMPS |No disconnect at motors motors_ |Service Entrance Overload___ | |

| |30" Panel Width Clearance__ |Wrong Conduit Type____ | |

| |30" Panel Front Clearance__ |Loose Conduit/Fittings____ | |

| |Penetorox on aluminum connections____ |NMSC Exposed_____ | |

| | | | |

| | | | |

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