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= Electrical Changes at 4180 SW 99th =

The following work done by homeowner Keith Lofstrom (me), and PC Electric of Newberg.

I trained in electronic engineering, and design integrated circuits. The voltages, currents, and sizes are all very much smaller, but many of the calculations are the same. I read books on home electrical work, and learned the most from "Ultimate Guide to Wiring", 6th Edition, by "Creative Homeowner". I also read large parts of the National Electrical Code, and various online resources. My goal is to do things right, and do things safe.

Many of the changes I made to old wiring are not strictly necessary, since the old stuff is grandfathered. But where I could do so without major disruption, I updated the wiring to match the current code, maximizing safety. When I added boxes, I made them bigger than necessary. I used grounded metal, insulated staples, and replaced electrical tape with wire nuts or crimp splices.

As I learned more, I improved my methods. For example, I used more crimp connectors. In a few cases, I used plastic boxes, where their water and corrosion resistant nature outweighed their lack of structural grounding.

In some cases, updating was difficult. For example, many receptacle boxes were the "half octagon" shapes with nails through them. There is no room in such boxes for GFCIs, so the whole branch got a GFCI breaker in the electrical subpanel.

The house as purchased had quite a few open boxes, some with dangling hot wires wrapped with decaying tape. Every open box we could find is either closed and wirenut-ted, or used for something new.

== The changes, in detail ==

=== Electrical Subpanels ===

The house originally had a Federal Pacific Stab-lok breaker box with failing breakers. These are a known fire risk. The connection to the meter was a large, nonmetallic cable to the meter box, hanging loose and unanchored outside. How that passed inspection, and survived 50 years, is difficult to imagine.

 * PC Electric replaced the meter box with a dual box and an outside 200A breaker, feeding a four wire main cable to a new Eaton Cutler-Hammer 200 amp, 40 position, BR style electrical subpanel in the basement. This feeds most of the house, as well as a 50A 4-3 NM cable to the garage.

  * The basement panel supplies approximately 20 branches in the house, including dishwasher, oven, cooktop, disposal, washer, dryer, receptacles, and 5 new branches added by Keith, discussed below.

  * Keith also added a BRSURGE surge protector. It is not ideally situated on the bus, but it is above the most sensitive branches.

  * The panel feeds an underground cable to the existing greenhouse and a subpanel out there. That duplex breaker is currently shut down, with a lockout and a nylon screw holding that branch off.

  * Bedroom receptacle branches have AFCI breakers, the basement-receptacle branches have GFCI breakers.

  * The upstairs and downstairs bathroom receptacles, each with it's own GFCI, share a new dedicated branch to the downstairs electrical subpanel.

   PC also added a 120 amp, 20 position BR style electrical subpanel in the garage, with a L14R 30A receptacle for a generator. The 50A feeder from the basement, and the 30A cable from the generator receptacle, feed 50A and 30A duplex breakers respectively, with a Cutler Hammer BRML mechanical lockout mechanism to prevent both breakers from being energized simultaneously.

  * The garage panel feeds four branches:

  * Garage bench sockets and bench light, garage door opener, and outside light. GFCI.

  * Garage electronics: FIOS network terminal, WIFI, firewall computer. GFCI.

  * Refrigerator/Freezer receptacles, cordless phone base. GFCI.

  * Gas furnace blower motor, downstairs. ''Not GFCI'' This branch was formerly running to the downstairs subpanel, with an old style NM cable stuffed through a series of 3/4" holes in the basement ceiling joists with 3 other NM cables and occasionally some phone and doorbell wire. The furnace cable was rerouted with new 12-2 NM to the garage subpanel, through different and uncrowded holes.

=== Basement Lighting ===

The two main rooms in the basement, recreation room and shop/storage room, were poorly lit with a few bare bulbs and three T-12 magnetic ballast strips.

 * The basement is now brightly lit with eighteen T-8 power-factor-corrected, 4 foot dual tube, high efficiency electronic ballast fixtures. 12 fixtures in the larger shop room, 6 fixtures in the smaller recreation room.

 * The shop, and the rec room, are each on new, separate 15A breakers in the downstairs electrical subpanel.

 * Rather than string romex through fixtures, groups of fixtures are wired together in star configurations, with large square electrical boxes used as splice boxes. Each fixture has it's own 14-2 romex running to a splice box, and the boxes are connected together with 12-2. Although we are not planning on covering the ceiling, the splice boxes are mounted to permit drywall covering.

 * The two remaining bulbs are no longer exposed, one covered with a glass fixture cover at the bottom of the stairs, and the other with a cage near the furnace.

 * The switch for the recreation room (now mostly a library) was behind the south door. That hole in the paneling has been repurposed as a keystone cover with two CAT6 ethernet receptacles and a telephone receptacle.

 * The light switches for the rectreation room now consist of a dual toggle box on the opening side of the south door (with one hole filled), and a dual toggle box on the opening side of the north door. The two south fixtures are controlled by a toggle in each box in a 3-way arrangement. One toggle in the north fixture controls 4 north fixtures in the library area. The separation allows lighting only the area needed.

 * The previous owner installed two really silly upwards-facing light-fixtures. These were replaced with two four-bulb light fixtures with CFLs. I would have preferred 2 foot T8s, less expensive and more efficient, but I was vetoed by my wife.

=== Other lighting ===

 * The garage has three new electronic ballast, 4 foot T8 fixtures. One is over the workbench, replacing an old T12 fixture (which had a wasp nest in it!!) connected to the garage "bench" branch. I added two 4 lamp fixtures, replacing a single bulb, and connected to the old fixture box (repurposed as a splice box) on a three way switch on branch 12. I added one additional four way switch inside the garage, at an appropriate height for the steps (the other two legacy switches are on the front garage wall and in the dining room. As part of this upgrade, I replaced the dining room switches.

 * I replaced the circular fluorescent fixture in the kitchen with a new T8 dual tube, connected to the old ceiling box but much better anchored to the ceiling.

 * The entry had a splice box in the ceiling, intended for an entry light but never connected. This splice box was crowded with a three-way splice of circuit 12, and an unused feed to an entry switch. This splice box was offset near a wall, and difficult to use.

  * I wired a new ceiling box, connected through the attic to the entry switch feed to a new entry ceiling fixture.

  * The freed-up space in the ceiling splice box now feeds an additional run of 14-2 in the attic to a new wall-mounted 2 foot single-lamp T8 fixture in the hall closet, operated with a pull switch in the closet.

 * The three bedroom closets had dangling, live wires, covered with tape but otherwise uncovered (50 years of that, sheesh!). I added a new 4 foot dual lamp T8 fixture, operated with a pull switch, in each closet, covering the open holes.

 * The outside light on the northwest corner of the house was used as a splice box for all the garage circuits. This was nasty. The grounds were corroded, and some of the receptacles were ungrounded. I pulled all the wires from this box, shortened them, and respliced them in new splice boxes in the garage. The outside light is now on a separate cable and switch, fed from these new splice boxes. All the grounds work.

 * Kitchen counter lights, Using wiremold, I extended one branch 30 receptacle box in the kitchen to provide power for a toggle switch, feeding an undercabinet line-powered LED strip near the center island. A similar feed off a receptacle in the garage feeds another switch and line powered LED strip in the northwest corner.

 * A third set of LED lights are powered off a 12VDC high efficiency adapter in the garage. These are connected through a door-mounted microswitch to power some in-cabinet lights illuminating a lazy susan inside a cabinet. While these are low voltage and power limited, I may reposition them mechanically to reduce the chances of shorts.

=== New receptacles ===

 * There were no outside receptacles. I added two new water-resistant receptacle boxes by the front garage door and the back door, powered by the garage receptacle and bench light branch. I used water resistant 20 amp receptacles.

 * There were insufficient receptacles in the upstairs bathroom, and they were not GFCI. I added 4 20A duplex under-counter outlets, the "feeding" one GFCI, in plastic boxes, and connected them to a new branch from the downstairs electrical subpanel.

 * This same new branch feeds a GFCI duplex receptacle in the basement bathroom.

 * I replaced every two prong duplex socket in the house (about 80% of them) with new 3 prong duplex sockets. Fortunately, all the boxes were grounded through grounded NM cable.

 * The basement receptacles on the south wall used to be fed from the same branch as the south wall bedroom receptacles, with wires running up and down zigzag (copper was cheap in 1960, and splice boxes expensive).

  * I rewired the south wall bedroom sockets to splice boxes and a new NM cable, and they are now on a AFCI breaker. I changed one bedroom receptacle to a larger box and a double duplex receptacle, as part of this rewiring.

  * I completely removed the old south wall basement receptacles, and ran two new GFCI branches to two sets of four dual duplex receptacles, one under each window. That makes 16 outlets under each window, which will be used for computers and other equipment in the downstairs shop/machine room. Too many receptacles is better than not enough.

  * These new receptacles are connected through DPDT switches to two optional medical grade isolation transformers (the wiring diagram is on the transformers).

   * From time to time, I work on switching power supplies, and it is convenient to "float the line", with both hot and neutral floating in relation to ground, so I can temporarily connect the negative side of the power supply input bridge to ground to inject signals and make measurements. With the transformers in-circuit, I can float the line. This manifests on the socket as power, but no connection between neutral and ground (ground is still there, though, just not a normally low-voltage neutral).

   * Most times, I am not working on power supply primaries, and the transformers are out of circuit, and not drawing energizing current.

 * Garage and kitchen closet receptacles added:

  * I put four new quad receptacle boxes in the garage, rewired one duplex receptacle behind the kitchen refrigerator, and added a quad receptacle box in the kitchen closet.

  * one garage quad receptacle is on the new refrigerator branch, feeding two refrigerators in the garage. The GFCI breaker for this branch is in the garage subpanel. I may add an alarm to this branch; if the GFCI trips, I want to know.

   * the same refrigerator branch feeds two kitchen receptacles, the kitchen refrigerator, and the broom closet. The broom closet branch feeds a dustbuster charger, and the main base unit for the cordless phones.

   * two garage quad receptacles are connected to the "computer branch", feeding the FIOS Optical Network Terminal (17 watts), the firewall computer (4 watts), and a Wifi access point and signal booster (12 watts). This wiring branch reaches around the corner of the main building, a structural post vital to the integrity of the building, Rather than drill through that, the cables connect through flexible armored sheath, running between splice boxes, instead.

   * A similar sheath connects around this corner to connect the front outside receptacles.

   * Another garage quad receptacle was added to branch 30, fed by the downstairs electrical subpanel. This provides power to the garage when the garage subpanel is disabled. It also acts as a splice box, feeding a wiremold switch to a line-powered LED undercounter light in the kitchen. Lastly, this quad receptacle feeds a 12 volt high efficiency inverter, which in turn feeds in-cabinet low-voltage switched LED lights inside kitchen cabinets.

=== Miscellaneous ===

 * For some bizarre reason, when the upstairs bathroom fan was on, a 40 volt high impedance potential developed between the faucets and the tub drain. The combination light/fan box was ungrounded.

  * The problem went away when I replaced the fan motor.

  * However, for redundant safety, I reconnected the light/fan box in the attic with new, grounded 12-3 cable, and also attached a grounding wire between faucets and drain, in the basement.

 * A switch in the living room fed an open box and a bell transformer in the attic near the fireplace, unconnected to anything besides dangling wires. I repurposed this switch to feed a roof vent fan in the attic, closed up boxes, etc.

 * I rewired the upstairs doorbell, closed an open box downstairs, and added a downstairs doorbell.

 * I removed all low voltage wiring associated with an old ADT security system. In the future, I expect to add webcams using Power Over Ethernet, as well as other low and medium voltage systems. These will be accessable over the internet, so I can monitor house safety while traveling.

 * I put two "temporary" fluorescent fixtures, connected through plugs and a power strip, in the attic. These are temporarily connected through a heavy
duty extension cord, through the access hatch, to a downstairs bedroom (AFCI) receptacle when I am working in the attic. Normally, these are completely disconnected.

 * PC Electric installed a new stovetop in the kitchen, properly attaching the pigtail.

 * The previous owner of 4180 installed a new oven. The pigtail from the oven came out in a different place, and in order to make it reach the splice box behind the drawers and under the counter, he let the splice box dangle in midair. I added a wooden diaphragm behind the drawers and attached the dangling box.

 * The disposal was installed with a dangling romex under the sink. I rewired that through armored cable to a new switch.

 * The downstairs shower had an open, non-waterproof ceiling fixture. Light removed and plated over, feed switch removed, wirenutted, and plated over.

 * The 240V air conditioner is powered through a 30 amp duplex breaker (slots 06 and 08) in the main downstairs subpanel. Those feed an old-style 8-2 multistrand cable, which is spliced to a more recent NM 10-2 cable near the stairs. The thinner cable then connects to the air conditioner (A Rheem RAKA 037JAZ 2.5T 30KBTU, 22Amps, manufactured 1996 ) through an outdoor connector and cartridge fuse by the downstairs back door. For some reason, the splice was made in a box mounted on the bottom of the stairs, about 3 feet off the ground. About 12 extra feet of cable, no armoring or covering.

  * For safety, abrasion resistance, and reduced length, I put a new splice box up in the basement-ceiling/main-floor joists, and reconnected these two cable segments overhead. I trimmed about 4 feet off the 8-2 cable and about 8 feet off the 10-2 cable.

  * One of the feed holes for the 8-2 cable is also stuffed with a couple of low voltage bell wires. I moved these to a new, small hole.


=== Low voltage wiring ===

The low voltage wiring, telephone and ethernet, has been rerouted down separate plastic cable channel.

 * The telephone is connected through two punchdown blocks at each end of the basement shop, to jacks in downstairs and upstairs low-voltage boxes. Most of the telephones in the house are cordless handsets, with two base stations, but there are phone wires to most of the same keystone boxes. As long as the FIOS optical network terminal is running, we can use hardwired POTS phones without other electricity.

 * The ethernet is more widely distributed, with 14 pairs of CAT6 running from an ethernet punchdown block and three 8 port gigabit switches in the basement to the garage (connecting to the firewall computer) and other low voltage boxes with keystone jacks in most rooms upstairs.

 * In time, I hope to build a battery-and-UPS-inverter system in the garage, feeding the computer electronics branch, so we can keep that running for a few days without grid power and without running the generator continuously.

=== Paneling and wiring protection ===

The Oregon structural code has not yet caught up with new knowledge about seismic risk, though engineers and professors from Oregon State and University of Washington are writing updates to the code. Oregon sits on the Cascadia subduction zone, a huge area running from British Columbia to Northern California where the Juan de Fuca tectonic plate slides under the North American plate. This massive area locks up, and releases approximately every 300 years, resulting in enormous Richter 9.5 earthquakes, more powerful than any historically recorded in North America. The 1000AD quake dumped a cubic mile of Larch Mountain into the Columbia, creating the "bridge of the gods" of indian lore. The 1700AD quake created a tsunami so powerful that the waves dumped sand on top of 100 foot cliffs.

The next quake will probably collapse a large part of Oregon's older buildings, with enormous loss of life. There is a 10% chance that will occur over the next 30 years. Our 1960 house was well built, with big strong beams and sill bolts, and can probably survive a Richter 7. However, a Richter 9, with 30 times the ground movement, could twist the house on its foundations, shearing
at the south basement wall and at the stairway.

 * There is no Oregon structural code to cover this risk, so I added extra reinforcement to the south basement wall. I added Simpson strong-tie metal forms at the base and top of every stud, some extra added studs, and a shear diaphragm of 5 ply, 3/4 inch plywood added for diagonal stiffness. This is attached with deck screws, the strongest I could find. These are removable for rough inspection. After rough inspection, I will cover the plywood with 5/8 inch firecode drywall, using drywall screws.

 * I will add similar stiffening and drywall to the stairway frame, and probably some stiffening gussets to the pillars connecting the central beam to pillars.

 * I am undecided as to whether I will plywood-stiffen the north wall between the kitchen and the roof. There is far less shear loading on this wall. It will get new sheetrock, whichever way I decide.

 * All in-wall wires, and the wires above the transformers and above the basement subpanel, will be covered.

 * Attic wires will be deeply buried under a foot of R-38 insulation batting.
No wires run across the top of ceiling beams, and most along-beam wires are underneath a board running down the spine of the house.

Electrical Changes at 4180 SW 99th

The following work done by homeowner Keith Lofstrom (me), and PC Electric of Newberg.

I trained in electronic engineering, and design integrated circuits. The voltages, currents, and sizes are all very much smaller, but many of the calculations are the same. I read books on home electrical work, and learned the most from "Ultimate Guide to Wiring", 6th Edition, by "Creative Homeowner". I also read large parts of the National Electrical Code, and various online resources. My goal is to do things right, and do things safe.

Many of the changes I made to old wiring are not strictly necessary, since the old stuff is grandfathered. But where I could do so without major disruption, I updated the wiring to match the current code, maximizing safety. When I added boxes, I made them bigger than necessary. I used grounded metal, insulated staples, and replaced electrical tape with wire nuts or crimp splices.

As I learned more, I improved my methods. For example, I used more crimp connectors. In a few cases, I used plastic boxes, where their water and corrosion resistant nature outweighed their lack of structural grounding.

In some cases, updating was difficult. For example, many receptacle boxes were the "half octagon" shapes with nails through them. There is no room in such boxes for GFCIs, so the whole branch got a GFCI breaker in the electrical subpanel.

The house as purchased had quite a few open boxes, some with dangling hot wires wrapped with decaying tape. Every open box we could find is either closed and wirenut-ted, or used for something new.

The changes, in detail

Electrical Subpanels

The house originally had a Federal Pacific Stab-lok breaker box with failing breakers. These are a known fire risk. The connection to the meter was a large, nonmetallic cable to the meter box, hanging loose and unanchored outside. How that passed inspection, and survived 50 years, is difficult to imagine.

  • PC Electric replaced the meter box with a dual box and an outside 200A breaker, feeding a four wire main cable to a new Eaton Cutler-Hammer 200 amp, 40 position, BR style electrical subpanel in the basement. This feeds most of the house, as well as a 50A 4-3 NM cable to the garage.
    • The basement panel supplies approximately 20 branches in the house, including dishwasher, oven, cooktop, disposal, washer, dryer, receptacles, and 5 new branches added by Keith, discussed below.
    • Keith also added a BRSURGE surge protector. It is not ideally situated on the bus, but it is above the most sensitive branches.
    • The panel feeds an underground cable to the existing greenhouse and a subpanel out there. That duplex breaker is currently shut down, with a lockout and a nylon screw holding that branch off.
    • Bedroom receptacle branches have AFCI breakers, the basement-receptacle branches have GFCI breakers.
    • The upstairs and downstairs bathroom receptacles, each with it's own GFCI, share a new dedicated branch to the downstairs electrical subpanel.
      • PC also added a 120 amp, 20 position BR style electrical subpanel in the garage, with a L14R 30A receptacle for a generator. The 50A feeder from the basement, and the 30A cable from the generator receptacle, feed 50A and 30A duplex breakers respectively, with a Cutler Hammer BRML mechanical lockout mechanism to prevent both breakers from being energized simultaneously.
    • The garage panel feeds four branches:
    • Garage bench sockets and bench light, garage door opener, and outside light. GFCI.
    • Garage electronics: FIOS network terminal, WIFI, firewall computer. GFCI.
    • Refrigerator/Freezer receptacles, cordless phone base. GFCI.
    • Gas furnace blower motor, downstairs. Not GFCI This branch was formerly running to the downstairs subpanel, with an old style NM cable stuffed through a series of 3/4" holes in the basement ceiling joists with 3 other NM cables and occasionally some phone and doorbell wire. The furnace cable was rerouted with new 12-2 NM to the garage subpanel, through different and uncrowded holes.

Basement Lighting

The two main rooms in the basement, recreation room and shop/storage room, were poorly lit with a few bare bulbs and three T-12 magnetic ballast strips.

  • The basement is now brightly lit with eighteen T-8 power-factor-corrected, 4 foot dual tube, high efficiency electronic ballast fixtures. 12 fixtures in the larger shop room, 6 fixtures in the smaller recreation room.
  • The shop, and the rec room, are each on new, separate 15A breakers in the downstairs electrical subpanel.
  • Rather than string romex through fixtures, groups of fixtures are wired together in star configurations, with large square electrical boxes used as splice boxes. Each fixture has it's own 14-2 romex running to a splice box, and the boxes are connected together with 12-2. Although we are not planning on covering the ceiling, the splice boxes are mounted to permit drywall covering.
  • The two remaining bulbs are no longer exposed, one covered with a glass fixture cover at the bottom of the stairs, and the other with a cage near the furnace.
  • The switch for the recreation room (now mostly a library) was behind the south door. That hole in the paneling has been repurposed as a keystone cover with two CAT6 ethernet receptacles and a telephone receptacle.
  • The light switches for the rectreation room now consist of a dual toggle box on the opening side of the south door (with one hole filled), and a dual toggle box on the opening side of the north door. The two south fixtures are controlled by a toggle in each box in a 3-way arrangement. One toggle in the north fixture controls 4 north fixtures in the library area. The separation allows lighting only the area needed.
  • The previous owner installed two really silly upwards-facing light-fixtures. These were replaced with two four-bulb light fixtures with CFLs. I would have preferred 2 foot T8s, less expensive and more efficient, but I was vetoed by my wife.

Other lighting

  • The garage has three new electronic ballast, 4 foot T8 fixtures. One is over the workbench, replacing an old T12 fixture (which had a wasp nest in it!!) connected to the garage "bench" branch. I added two 4 lamp fixtures, replacing a single bulb, and connected to the old fixture box (repurposed as a splice box) on a three way switch on branch 12. I added one additional four way switch inside the garage, at an appropriate height for the steps (the other two legacy switches are on the front garage wall and in the dining room. As part of this upgrade, I replaced the dining room switches.
  • I replaced the circular fluorescent fixture in the kitchen with a new T8 dual tube, connected to the old ceiling box but much better anchored to the ceiling.
  • The entry had a splice box in the ceiling, intended for an entry light but never connected. This splice box was crowded with a three-way splice of circuit 12, and an unused feed to an entry switch. This splice box was offset near a wall, and difficult to use.
    • I wired a new ceiling box, connected through the attic to the entry switch feed to a new entry ceiling fixture.
    • The freed-up space in the ceiling splice box now feeds an additional run of 14-2 in the attic to a new wall-mounted 2 foot single-lamp T8 fixture in the hall closet, operated with a pull switch in the closet.
  • The three bedroom closets had dangling, live wires, covered with tape but otherwise uncovered (50 years of that, sheesh!). I added a new 4 foot dual lamp T8 fixture, operated with a pull switch, in each closet, covering the open holes.
  • The outside light on the northwest corner of the house was used as a splice box for all the garage circuits. This was nasty. The grounds were corroded, and some of the receptacles were ungrounded. I pulled all the wires from this box, shortened them, and respliced them in new splice boxes in the garage. The outside light is now on a separate cable and switch, fed from these new splice boxes. All the grounds work.
  • Kitchen counter lights, Using wiremold, I extended one branch 30 receptacle box in the kitchen to provide power for a toggle switch, feeding an undercabinet line-powered LED strip near the center island. A similar feed off a receptacle in the garage feeds another switch and line powered LED strip in the northwest corner.
  • A third set of LED lights are powered off a 12VDC high efficiency adapter in the garage. These are connected through a door-mounted microswitch to power some in-cabinet lights illuminating a lazy susan inside a cabinet. While these are low voltage and power limited, I may reposition them mechanically to reduce the chances of shorts.

New receptacles

  • There were no outside receptacles. I added two new water-resistant receptacle boxes by the front garage door and the back door, powered by the garage receptacle and bench light branch. I used water resistant 20 amp receptacles.
  • There were insufficient receptacles in the upstairs bathroom, and they were not GFCI. I added 4 20A duplex under-counter outlets, the "feeding" one GFCI, in plastic boxes, and connected them to a new branch from the downstairs electrical subpanel.
  • This same new branch feeds a GFCI duplex receptacle in the basement bathroom.
  • I replaced every two prong duplex socket in the house (about 80% of them) with new 3 prong duplex sockets. Fortunately, all the boxes were grounded through grounded NM cable.
  • The basement receptacles on the south wall used to be fed from the same branch as the south wall bedroom receptacles, with wires running up and down zigzag (copper was cheap in 1960, and splice boxes expensive).
    • I rewired the south wall bedroom sockets to splice boxes and a new NM cable, and they are now on a AFCI breaker. I changed one bedroom receptacle to a larger box and a double duplex receptacle, as part of this rewiring.
    • I completely removed the old south wall basement receptacles, and ran two new GFCI branches to two sets of four dual duplex receptacles, one under each window. That makes 16 outlets under each window, which will be used for computers and other equipment in the downstairs shop/machine room. Too many receptacles is better than not enough.
    • These new receptacles are connected through DPDT switches to two optional medical grade isolation transformers (the wiring diagram is on the transformers).
      • From time to time, I work on switching power supplies, and it is convenient to "float the line", with both hot and neutral floating in relation to ground, so I can temporarily connect the negative side of the power supply input bridge to ground to inject signals and make measurements. With the transformers in-circuit, I can float the line. This manifests on the socket as power, but no connection between neutral and ground (ground is still there, though, just not a normally low-voltage neutral).
      • Most times, I am not working on power supply primaries, and the transformers are out of circuit, and not drawing energizing current.
  • Garage and kitchen closet receptacles added:
    • I put four new quad receptacle boxes in the garage, rewired one duplex receptacle behind the kitchen refrigerator, and added a quad receptacle box in the kitchen closet.
    • one garage quad receptacle is on the new refrigerator branch, feeding two refrigerators in the garage. The GFCI breaker for this branch is in the garage subpanel. I may add an alarm to this branch; if the GFCI trips, I want to know.
      • the same refrigerator branch feeds two kitchen receptacles, the kitchen refrigerator, and the broom closet. The broom closet branch feeds a dustbuster charger, and the main base unit for the cordless phones.
      • two garage quad receptacles are connected to the "computer branch", feeding the FIOS Optical Network Terminal (17 watts), the firewall computer (4 watts), and a Wifi access point and signal booster (12 watts). This wiring branch reaches around the corner of the main building, a structural post vital to the integrity of the building, Rather than drill through that, the cables connect through flexible armored sheath, running between splice boxes, instead.
      • A similar sheath connects around this corner to connect the front outside receptacles.
      • Another garage quad receptacle was added to branch 30, fed by the downstairs electrical subpanel. This provides power to the garage when the garage subpanel is disabled. It also acts as a splice box, feeding a wiremold switch to a line-powered LED undercounter light in the kitchen. Lastly, this quad receptacle feeds a 12 volt high efficiency inverter, which in turn feeds in-cabinet low-voltage switched LED lights inside kitchen cabinets.

Miscellaneous

  • For some bizarre reason, when the upstairs bathroom fan was on, a 40 volt high impedance potential developed between the faucets and the tub drain. The combination light/fan box was ungrounded.
    • The problem went away when I replaced the fan motor.
    • However, for redundant safety, I reconnected the light/fan box in the attic with new, grounded 12-3 cable, and also attached a grounding wire between faucets and drain, in the basement.
  • A switch in the living room fed an open box and a bell transformer in the attic near the fireplace, unconnected to anything besides dangling wires. I repurposed this switch to feed a roof vent fan in the attic, closed up boxes, etc.
  • I rewired the upstairs doorbell, closed an open box downstairs, and added a downstairs doorbell.
  • I removed all low voltage wiring associated with an old ADT security system. In the future, I expect to add webcams using Power Over Ethernet, as well as other low and medium voltage systems. These will be accessable over the internet, so I can monitor house safety while traveling.
  • I put two "temporary" fluorescent fixtures, connected through plugs and a power strip, in the attic. These are temporarily connected through a heavy

duty extension cord, through the access hatch, to a downstairs bedroom (AFCI) receptacle when I am working in the attic. Normally, these are completely disconnected.

  • PC Electric installed a new stovetop in the kitchen, properly attaching the pigtail.
  • The previous owner of 4180 installed a new oven. The pigtail from the oven came out in a different place, and in order to make it reach the splice box behind the drawers and under the counter, he let the splice box dangle in midair. I added a wooden diaphragm behind the drawers and attached the dangling box.
  • The disposal was installed with a dangling romex under the sink. I rewired that through armored cable to a new switch.
  • The downstairs shower had an open, non-waterproof ceiling fixture. Light removed and plated over, feed switch removed, wirenutted, and plated over.
  • The 240V air conditioner is powered through a 30 amp duplex breaker (slots 06 and 08) in the main downstairs subpanel. Those feed an old-style 8-2 multistrand cable, which is spliced to a more recent NM 10-2 cable near the stairs. The thinner cable then connects to the air conditioner (A Rheem RAKA 037JAZ 2.5T 30KBTU, 22Amps, manufactured 1996 ) through an outdoor connector and cartridge fuse by the downstairs back door. For some reason, the splice was made in a box mounted on the bottom of the stairs, about 3 feet off the ground. About 12 extra feet of cable, no armoring or covering.
    • For safety, abrasion resistance, and reduced length, I put a new splice box up in the basement-ceiling/main-floor joists, and reconnected these two cable segments overhead. I trimmed about 4 feet off the 8-2 cable and about 8 feet off the 10-2 cable.
    • One of the feed holes for the 8-2 cable is also stuffed with a couple of low voltage bell wires. I moved these to a new, small hole.

Low voltage wiring

The low voltage wiring, telephone and ethernet, has been rerouted down separate plastic cable channel.

  • The telephone is connected through two punchdown blocks at each end of the basement shop, to jacks in downstairs and upstairs low-voltage boxes. Most of the telephones in the house are cordless handsets, with two base stations, but there are phone wires to most of the same keystone boxes. As long as the FIOS optical network terminal is running, we can use hardwired POTS phones without other electricity.
  • The ethernet is more widely distributed, with 14 pairs of CAT6 running from an ethernet punchdown block and three 8 port gigabit switches in the basement to the garage (connecting to the firewall computer) and other low voltage boxes with keystone jacks in most rooms upstairs.
  • In time, I hope to build a battery-and-UPS-inverter system in the garage, feeding the computer electronics branch, so we can keep that running for a few days without grid power and without running the generator continuously.

Paneling and wiring protection

The Oregon structural code has not yet caught up with new knowledge about seismic risk, though engineers and professors from Oregon State and University of Washington are writing updates to the code. Oregon sits on the Cascadia subduction zone, a huge area running from British Columbia to Northern California where the Juan de Fuca tectonic plate slides under the North American plate. This massive area locks up, and releases approximately every 300 years, resulting in enormous Richter 9.5 earthquakes, more powerful than any historically recorded in North America. The 1000AD quake dumped a cubic mile of Larch Mountain into the Columbia, creating the "bridge of the gods" of indian lore. The 1700AD quake created a tsunami so powerful that the waves dumped sand on top of 100 foot cliffs.

The next quake will probably collapse a large part of Oregon's older buildings, with enormous loss of life. There is a 10% chance that will occur over the next 30 years. Our 1960 house was well built, with big strong beams and sill bolts, and can probably survive a Richter 7. However, a Richter 9, with 30 times the ground movement, could twist the house on its foundations, shearing at the south basement wall and at the stairway.

  • There is no Oregon structural code to cover this risk, so I added extra reinforcement to the south basement wall. I added Simpson strong-tie metal forms at the base and top of every stud, some extra added studs, and a shear diaphragm of 5 ply, 3/4 inch plywood added for diagonal stiffness. This is attached with deck screws, the strongest I could find. These are removable for rough inspection. After rough inspection, I will cover the plywood with 5/8 inch firecode drywall, using drywall screws.
  • I will add similar stiffening and drywall to the stairway frame, and probably some stiffening gussets to the pillars connecting the central beam to pillars.
  • I am undecided as to whether I will plywood-stiffen the north wall between the kitchen and the roof. There is far less shear loading on this wall. It will get new sheetrock, whichever way I decide.
  • All in-wall wires, and the wires above the transformers and above the basement subpanel, will be covered.
  • Attic wires will be deeply buried under a foot of R-38 insulation batting.

No wires run across the top of ceiling beams, and most along-beam wires are underneath a board running down the spine of the house.

RoofLeak (last edited 2011-01-23 00:20:53 by KeithLofstrom)