Residential Maintenance Guide

Electrical Maintenance

Service Entrance

Your local utility company supplies electricity to your home by means of the service entrance cable. The cable can be brought in overhead or underground. The size of the cable determines how much electricity is available to the home. The minimum service size on new construction is 100 amps.

There are many houses with a 60 amp capacity that still provide adequate service. Normal household lighting and most small appliances will usually draw under 60 amps. The addition of electric stoves, electric clothes dryers, or AC units may push the system to capacity. At this point, updating to 100 amps should be seriously considered.

Service Entrance Maintenance

Periodically inspect the service cable for fraying or cracking.
Be sure that the service cable and meter are well secured to the home.

Ever wonder how the utility company calculates your energy consumption?

Power is measured in watts, and is calculated by multiplying the voltage times the current. For example, a 1200 watt dishwasher, when subjected to 120 volts, will allow 10 amps to flow through it. A house with a 240 volt supply and 100 amp main fuses may have the capability of 24,000 watts. 1000 watts is referred to as a kilowatt.

If 1000 watts are used continuously for one hour this is referred to as a kilowatt hour. This is how electricity is purchased from the utility company. The electric meter records kilowatt hours used in the house. If one kWh cost ten cents and 1000 kWhs are used in a month, the electric bill would be $100.00.

Service Panel

Electricity is carried from the service cable to the service panel, through the fuse or circuit breaker, and distributed to the individual branch circuits.

Fuses and breakers serve the same function; They both protect against overload situations. The advantage of a circuit breaker is it can be reset after an overload situation occurs whereas a fuse has to be replaced.

FUSES: Two common types of fuses used today are: the Time Delay, type D and the type S.

Type D fuses are time delayed devices that do not blow immediately. They will, for a short time, allow more than the rated current to flow through the circuit. Some devices will draw extra current upon startup. The time delay feature can prevent nuisance blowing during these brief electrical loads.

Type S fuses are screw-in type fuses that are not interchangeable. This means that the wrong size fuse will not fit into the fuse holder. This provides added safety over the older fuses which could be interchanged.

The most common deficiency found in many homes is an inadequately sized fuse for the circuit wire. This is an unsafe situation and should be corrected promptly.

CIRCUIT BREAKERS: Most circuit breakers can be tripped by moving the switch to the middle position, others to the off position. Generally, it is easy to determine which breaker has tripped. To reset, simply switch the breaker to the “off” position then back to the “on” position.

Service Panel Maintenance

Annually inspect the inside of the panel for signs of rust, water penetration, and scorched wires.
Trip the circuit breakers once a year. Ground fault breakers, once a month. If fuses are used, be sure they are screwed in tightly.

Many homeowners feel confident they can handle electrical repairs. It they can handle electrical repairs. It they can handle electrical repairs. It they can handle electrical repairs.

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Keep yourself and your family safe!

Outlets

Until about 1950 most electrical outlets were ungrounded. The outlets had only two slots; one connected to the black wire and one connected to the white. After 1960, grounded outlets (three slots) became popular and are now mandatory. Rather than flowing through a person, the ground wire is a safety path for electricity to follow in case of a malfunction in the system.

There are many two slotted outlets that have been upgraded to three slot without providing a ground wire.

This has no benefit, and may be misleading when plugging a three-pronged device into an upgraded but ungrounded outlet.

GFCI outlets, or ground fault circuit interrupters, are special devices that turn the power off to a circuit when a voltage leak is detected. If there is a defect in the system, electricity may flow to a dangerous place and may not be enough to trip a breaker or blow a fuse. If a person becomes the path for stray current, it can be potentially hazardous. A ground fault circuit interrupter prevents this from happening by measuring the current going out against the current coming in. If the difference is more than .005 amps, the system will be shut off.

It makes sense to install GFCI outlets wherever water and electricity come close together.

Currently, GFCI outlets are required at all exterior outlets, bathrooms, kitchens, and pool equipment.

Outlet Maintenance

Periodically inspect outlets and switches for damage, scorching, and looseness.
Trip all GFCI outlets monthly.

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