One of the systems I inspect in the home is the electrical system. Electrical issues can be very serious as they can start a fire and in extreme cases electrocute you. Here is a small example of issues your inspector must catch.
There is some serious corrosion going on here. This is a fire hazard as the electrical flow will be very poor going through this. Should you ask for a lot of juice the wire will heat up. Antioxidant paste is absent on the SEC wire.
This photo shows the SEC (service entrance cable)is undersized. the main breaker will allow 200 ampere into the system before tripping – the wire is only rated for 100 ampere. The wires will heat up like a toaster with the right (wrong) load applied!
These photos show what is known as a shared neutral circuit. The black wire and the red wire each carry an electrical load, witch should be on opposing legs (see photo above). When one leg (L 1 or line 1) is energized the other (L 2 or line 2) is not. The electricity cycles on and off opposingly (alternating current) 60 time a second (60 hertz). The electrical current goes to a device in the black or red wires and returns through the grounded (neutral) white wire.
Here both the black and red wires are on the same leg.These wires are rated for 15 amperes each. 15 for the black, 15 for the red. That is putting 30 amperes on the white wire that is also rated for 15 amperes. Fire hazard.
Double taps are a common defect. This is when 2 (two) conductors are installed under the lug of a single breaker. This is not permitted*. As current passes through the conductor (wire) it heats up, metals expand as they heat up and contract when they cool off – (nothing you or I would notice). When 2 wires are together, they both heat up and expand into each other, copper is a soft metal and will compress and elongate, when they cool and contract there is less metal under the lug. Again, nothing you or I would notice. Repeat this enough times and the wire will become loose under the lug – Yes , I have seen it many times – loose wires have a tendency to arc, arcs have a tendency to start fires. Yes they can start fires in the panel, lots of flammable plastics in there. A double tap before the main disconnect is double trouble, these conductors also have the issue of not being protected from over current and there is no way to de-energize them. There hot – Always (unless the power to the house is disconnected at the meter), having unprotected wires in the building structure is a fire hazard!
The Standard Lug breaker to the left as you can see would require both wires to be under the same area of compression from the lug. The Square D breaker has 2 slots for wires and this is the exception to the rule.
The exception to this rule is if the breaker is rated for 2 conductors, Square D breakers are rated and listed for 2 conductors.