Temporary Power Setup and Teardown
Purpose
Temporary power is a complete electrical system that everyone on site treats as an accessory. It gets built in a morning, serves five trades who cannot tell you where its ground rod is, lives outdoors through a winter, and then gets removed by whoever is left at the end.
The injury pattern is not even across that life. Setup is done by electricians who know what they are doing; the middle of the job is covered by ground-fault protection as long as somebody keeps testing. Teardown happens under schedule pressure on a system everyone assumes went dead when the permanent service came alive, and breaking that assumption is step 10's whole job.
Scope
Covers temporary electrical services and distribution on construction and remodel sites, from the utility pole or existing permanent service to the receptacle, at 120/240 V single phase.
Does not cover generator-supplied temporary power, which adds bonding and transfer questions this procedure does not address, or permanent service installation, which the service-upgrade load calculation SOP owns.
Roles and responsibilities
| Role | Owns | Hands off |
|---|---|---|
| Lead electrician | Setup steps 1 through 7 and the teardown at step 10 | A written statement to the GC of what is protected, by which method, and who tests it |
| Competent person | The assured grounding program or the GFCI inspection cycle | Every test logged with date and result, failed equipment pulled the same hour |
| General contractor | Site control, trades off the pole, notice before permanent power is energized | Confirms the transition date in writing so step 9's overlap is planned, not discovered |
| Supervising master | Method selection at step 5 and any deviation | Owns the call when a site wants temp power past the permanent cutover |
Procedure
Confirm the utility's temporary service requirements and the point of attachment before material is ordered. Acceptance: the utility's written temp service spec in hand, the approved location and service point height, and the AHJ permit filed. Wrong looks like a pole built to the last utility's standard in a different territory. Stop rule: no written spec, no build - utilities differ on pole depth, bracing, weatherhead height and conductor entry, and a rejected pole is rebuilt on the shop's time. Hazard: none yet, which is the point of settling it on paper.
Site the pole clear of overhead conductors and confirm the excavation before anyone digs. Acceptance: the pole and every position a person can occupy during the raise sit outside the minimum approach distance - 10 feet for unqualified persons on lines up to 50 kV, per 29 CFR 1910.333(c)(3) - and the one-call locate is marked. Wrong looks like a pole raised under a service drop because that is where the meter had to go. Stop rule: if the geometry cannot clear the lines, the utility de-energizes or covers them before the pole moves. Hazard: a pole under a raise is a conductive object in human hands, and contact with an energized line at that moment is a fatality, not an injury.
Build the pole with the bracing, supports and enclosure ratings the environment requires. Acceptance: braced against overturning per the utility spec, nothing under tension at a termination, enclosures rated for the wet location they occupy, and no conductor bare or exposed, per NEC 590.4. Wrong looks like a panel screwed to a post with cables hanging off their connectors. Stop rule: a temporary installation carries the same requirements for supports, terminations and enclosure integrity as a permanent one - temporary is about duration, not workmanship. Hazard: the pole is worked from a ladder on uneven ground, so it is footed and tied off before anyone climbs.
Establish the grounding electrode and bond the enclosures. Acceptance: electrode installed and connected per NEC Article 250, the grounding electrode conductor sized to the service conductors, and continuity from every receptacle's grounding contact back to the electrode measured and recorded rather than assumed. Wrong looks like a rod driven and a conductor wrapped around it. Stop rule: an unverified grounding path undermines whichever method step 5 picks, so it is proved before anything is energized. Hazard: driving a rod is a strike hazard for whoever holds it, and the step 2 locate governs where it goes.
Select the ground-fault protection method and register it in writing, because the two carry different obligations. Acceptance: either GFCI protection on every 125 V single-phase 15, 20 and 30 A receptacle outlet not part of the permanent wiring, per 29 CFR 1926.404(b)(1)(ii), or an assured equipment grounding conductor program under 1926.404(b)(1)(iii) with a written description, a named competent person and the test records on site. Wrong looks like a site with GFCI on some circuits calling that the program. Stop rule: the assured grounding program is the option with a named person and a test schedule, not the easier one; a site that will not name the person takes the GFCI route. Hazard: the consequence of choosing wrong lands on the trade holding a damaged cord.
Test every cord set, receptacle and plug-connected tool before first use. Acceptance: each item shows continuity of the equipment grounding conductor and correct terminal connections at both ends, logged by item. Under 1926.404(b)(1)(iii) tests are required before first use, before return to service after repairs, after any incident suspected of causing damage, and at intervals not exceeding 3 months, except fixed cord sets and receptacles not exposed to damage, at 6 months. Wrong looks like a visual inspection recorded as a test. Stop rule: a failed item is tagged and physically removed from the site the same hour, because a tagged cord left on the pole gets used. Hazard: the cord is tested disconnected from the supply - one tested with its other end plugged in is an energized conductor in somebody's hand.
Energize, verify each circuit, and label the whole installation. Acceptance: each circuit verified for correct polarity, correct grounding and correct GFCI function on the device's own test button, the panel directory complete, and a sign at the pole naming the shop, the emergency contact and the protection method in use. Wrong looks like an energized temp panel whose directory five trades then guess at. Stop rule: an unlabeled temp panel is not handed over - labeling is part of energization. Hazard: this is a switching operation into gear just assembled, so covers on, body out of line with the panel face, assessed PPE on.
Run the inspection and test cycle for the whole life of the job, and record every cycle. Acceptance: the named competent person completes the scheduled tests on time and logs them, the log lives on site rather than in an office, and cords and tools get a daily visual check for external defects before each shift. Wrong looks like a program set up in month one and last tested in month one. Stop rule: a missed interval is not backfilled with a note - the equipment is tested before it is used again. Hazard: the site changes around the installation, so a cord that ran along a wall in March may be run over by a lift in June, and the visual inspection catches it.
Plan the transition to permanent power so no period exists where both are live and nobody owns either. Acceptance: a written date, a named person on the GC side, and a sequence stating which circuits move when. Wrong looks like a permanent service energized on a Friday with the temp pole still hot and every trade still plugged into it. Stop rule: temp power is not left energized as a convenience once the permanent service is in use unless someone is still named as its competent person and the test cycle still runs; NEC 590.3(D) requires temporary wiring removed immediately upon completion of the purpose it served. Hazard: two live systems on one site is how a conductor gets cut on the assumption it belongs to the other.
Tear down as a de-energized job with the same isolation discipline as any other. Acceptance: the utility disconnects or the supply is opened and locked, and every conductor is proved dead at the point of work with an instrument checked live before and after per NFPA 70E-2021 120.5, before anything is cut, coiled or pulled. Wrong looks like a crew cutting the drop because the meter was pulled last week. Stop rule: nobody's memory of a de-energization substitutes for a test at the point of work, even when the person who de-energized it is standing there. Hazard: a temp service backfed from a generator, or one whose disconnect was restored for another trade, is live exactly when the crew least expects it, and the conductor being coiled is in both hands.
The record this produces
One temporary power file per site. Fields: utility spec and permit references; pole location with clearance to overhead conductors; grounding electrode type with measured continuity result; protection method with named competent person; an equipment register of every cord set, receptacle and tool with a tag number; every test with date, result and tester; the daily visual inspection log; the energization verification; the transition plan with date and contact; the teardown record with its isolation verification. The register is what makes the log mean anything: "cords tested" proves nothing, while fourteen tagged items with fourteen dated results prove the interval was met.
Worked pass: four-unit townhouse site, 100 A temp service
Step 1 obtained the utility's temp service sheet and the permit. Step 2 sited the pole 22 feet from the nearest overhead conductor, clearing the 10 foot approach distance during the raise; the one-call locate marked a gas line 9 feet from the intended electrode, so the rod moved.
Service size went on the sheet as a written assumption, not a code calculation, since no NEC demand method covers a construction tool inventory: a 66 A tool list at a logged 0.7 simultaneity factor, 23.1 A per 120 V leg, against the utility's 100 A standard.
Step 5 selected the assured grounding program, because the site's heavy corded tools were tripping GFCI devices on long cord runs, and the GC named a competent person in writing.
Step 6 fails. Fourteen cord sets were registered and tested before first use. Eleven passed. Two showed an open equipment grounding conductor, and one showed the terminals reversed at the female end, which puts the ungrounded conductor on the grounding contact of every tool plugged into it. Three of fourteen, roughly 21 percent of the cords on site on day one, and none of the three looked damaged.
The stop rule fired as written: all three were tagged and removed from the site that hour rather than set aside for repair, because a tagged cord on a jobsite gets picked up. Their circuit was not energized for use until every cord in that area had been tested.
That finding changed the rest of the job. The competent person moved the cord set interval from the 3 month maximum to monthly and logged the reason, a shortening rather than a deviation, so it needed no approval.
Step 9's transition ran on a Tuesday: permanent panels energized in the morning, temp pole de-energized and locked at noon. Step 10's teardown two days later still ran the full isolation - supply opened and locked, every conductor proved dead at the point of work with a meter verified live before and after - despite three people being certain the pole had been dead since Tuesday. It had been. The verification cost four minutes and is why the record can say so.
References
- NEC (NFPA 70) Article 590, temporary installations: 590.3(D) removal on completion, 590.4 general requirements, 590.6 ground-fault protection for personnel
- 29 CFR 1926.404(b)(1) for construction work: the GFCI option at (ii), the assured equipment grounding conductor program at (iii) with its test triggers and 3 month and 6 month maximum intervals
- 29 CFR 1910.333(c)(3), minimum approach distances near overhead lines, binding the shop for its own employees during the pole raise at step 2
- NFPA 70E-2021, 120.5, for the absence-of-voltage verification at teardown, in the edition your electrical safety program has adopted
- NEC (NFPA 70) Article 250 for the grounding electrode system and bonding at step 4