Panel bonding jumper missing / 200A Service

A green-colored screw should thread into the heavy gauge steel of this 200A service panel enclosure, securing the bonding jumper. At the center of the highlighted area in the photo, one can see that the screw was either removed or never installed.

This threaded ground bonding location ensures that the metal panel enclosure remains at zero voltage to the building and service grounding systems, and helps ensure that a low-impedance path for fault current on the panel enclosure will trip a breaker before serious damage occurs. A poor connection here could result in a high-impedance path for fault current. An ungrounded (‘hot’) conductor could contact the panel enclosure and discharge to ground through this poor connection at relatively low levels of current not sufficient to trip the breaker protecting the circuit. At least two hazards would result:

1. The connection missing the screw could heat up and melt adjacent wire insulation, causing more trouble, or ignite the wooden surface on which the panel is mounted.
2. The panel enclosure would remain energized until the fault is cleared, and could electrocute someone.

Office fit-out with cubicles

This office electrical fit-out project involved relocation and addition of ceiling-hung, 220V space heaters, salvaged pendant fixtures and connection of multiple circuits to a set of internally-wired cubicle branch circuits serving receptacles.

200A underground service upgrade

This was a straightforward 200A service upgrade job on the service side, but a nest of badly labeled branch circuit conductors in a shared raceway (3/4″ conduit) made re-connection at the new service disconnect/breaker panel more difficult than it could have been.

I include a GFCI receptacle with service equipment replacements/upgrades, and in this case I also installed a switched utility service light to facilitate finding breakers or further work at the service disconnect/distribution breaker panel location.

Pneumatic Elevator and Misc. Renovation

This project involved 30A, 220V power and telephone callbox wiring to supply an innovative pneumatic elevator tube lift that works on the same principles as the deposit tube at a drive-through teller or the cash register drop tubes at a big-box home improvement store like Home Depot.

Overall, the project involved complex coordination over a period of months, with the general contractor’s several trades. There were also a mix of new and antique/reused materials, and an unusual HVAC implementation involving installation and configuration of a differential thermostat to draw conditioned air from the main areas of the house to the 1st Floor foyer area adjacent to the garage, when the temperature differential reaches a set threshold. Read more >>

Frayed service cable / power quality

Frayed service cable / power quality

What type of electric service cable damage are you looking out for?

If you can see exposed aluminum strands on your service entrance cable, it has frayed to the point where you should replace it. Cost may vary from $750 – $2200, depending on your service capacity (usually between 100A – 200A for residential electric accounts) and the capacity of your replacement service (for those wanting central air conditioning, an upgrade from 100A to 150A or 200A will often be needed; subsequent solar PV or micro wind power installations over 5kW capacity may be cheaper to install if the existing service is larger than 100A).

More on causes and effects of worn electric service entrance cable >>

Fuse cabinet as distribution panel

Fuse cabinet as distribution panel

Many homes in West Philadelphia feature a distribution panel remote from the main service equipment. In older installations, this may be a wooden cabinet with a picture-framed wooden or glass-pane door, usually located in a stair- or hallway, and lined with a felt-like friable material that may be asbestos.

Several fuse-holder modules provide for branch circuit over-current protection. Unlike with modern wiring, the fuses may protect both the grounded (neutral) and ungrounded (‘hot’) conductors of 120V circuits, so a single circuit may have two fuses in it.

These fuse cabinets may not meet the demands of modern electrical usage

More on working with, or replacing old fuse cabinet type distribution panels >>

Rewire house: West Philly twin

This project broke down into three main phases, with a 200A service upgrade, rewiring the 2nd floor  before move-in, while water-damaged ceilings were being repaired, and the First Floor and Kitchen undertaken during occupancy, months later.

200A Service Upgrade

The 200A panel upgrade involved replacing the service cable drop, meter pan, and carefully preserving a special timer-controlled metering setup for a discontinued but grand-fathered tariff featuring time of use rates that provide 1/2-price energy for water heating, but no energy at all from 10am – 4pm.

Read more >>

CFL’s are good, but not great

First, let me say that I recommend using CFL’s. It’s just that I wonder if mandating conversion from incandescents to new lighting technologies shouldn’t be coupled with some better education about the new lamps.

Soon to be mandated to exclusion of incandescents, are CFL’s as good as people make them out to be? CFL’s have several under-publicized issues that all customers should be aware of.

More on mercury and dimming issues with CFL lamps >>

Relocated ceiling fixture – no plaster repair

The challenge: install a new, room-centered ceiling fan/light location extended from an off-center existing ceiling fixture three joist-bays forward of center (front to back) and hard to the exterior wall (left to right).

The results? A seamless installation at the minimum quoted pricing scenario, by fishing new cable through holes blind-drilled six feet diagonally through three joists.

Drilled through 3 ceiling joists to fish NM-B cable from existing to new ceiling fixture location.

Original price quote:

I quoted $50 to install a replacement fixture in the current location, plus $75 to move to the center of the room’s NE ‘alcove’ area (within the same joist bay as the original location). To move to the actual center of the room, change that $75 to $150, and budget for some ceiling repair/paint in case I am unable to drill through two joists and get the wire to fish through them, without opening the ceiling to access the cavities between the joists. Note that location may have to be as much as 14″ forward or back of center, so that the wiring box can install on a structural joist and provide safe support for the ceiling fan. The additional charge for plaster repair, if necessary, would be $75, and paint would be on you. I don’t really want to do plaster repair, so I’m happy to put that on you, too.

Actual amount invoiced: $150.

Electrical System Review 20110127_S49th

xxxx S 49th St., Philadelphia, PA

Inspection conducted January 27, 2011 pursuant to settlement contingencies in the sale of a home

by

Robert Monk

Robert Monk Electric

Philadelphia Lic. #35849

PA HIC #060608

CONTENTS

I     SUMMARY

II   SCOPE OF REVIEW

III  ITEM DETAILS

IV  PROPOSALS & ESTIMATES

V   CONTINGENCY FOR CERTIFICATION TO INSURER

VI  PHOTOS

Read more >>

Electrical System Review 20110330_S49th

Following is copied from a formal presentation resulting from by-the-way observations during a service call for a single branch circuit outage…

CONTENTS

1. Summary

2. Scope of Review

3. Item Details & Recommendations w/ Estimates

4. Illustrations

I SUMMARY

The electrical system needs a 2-year program of gradual upgrade and repair that might cost between $1000 and $5000. The basement ceiling is a rat’s nest and the service equipment has been incompletely consolidated from four (4) 60A services to one (1) 60A service currently in use plus another that is energized but not in use. With multiple adults in the large building, the service should be 100A minimum; two 60A services would be more than enough, if loads were balanced across them, but this involves an ‘overhead’ of an additional $5/month to maintain unneeded separate billing for the two metered accounts. A single, 100- , 150- or 200A service would be ideal for the current use, but would involve higher up-front costs.

Service entrance cables from the abandoned meters have been disconnected inside the multi-gang meters enclosure, but remain a hazard because of their proximity inside the enclosure to live terminals that have no over-current protection (breaker or fuse). These should be removed or terminated in proper enclosures, as part of any work to complete the electrical service equipment.

Other specific electrical problems I observed in this building include: open wire enclosures in basement ceiling and 2nd floor switch box. Abandoned receptacle location at Dining Room north, NM-B (“Romex”) cable subject to damage where run loose in attic, frayed cables in basement ceiling, rusted conduit at Exterior north, near service meters, missing GFCI protection at Basement laundry area, missing bushing where service drop cable at Exterior north exits protective sleeve conduit, and some non-electrical wood rotted on Exterior north window trim and siding.

Also, the basement has a damp floor and smells strongly of mold.

Read more >>