Square D main panel and Cutler Hammer sub panel

Inspected a home with a Square D main service panel and a Cutler Hammer sub panel (30 amp breaker from the main). I believe that the Cutler Hammer sub panel was the original installed in the home and converted to a sub panel when the Square D panel was added. The home was a 1951 build.

In the Square D panel, a 30 amp breaker on the upper right side (labeled for dryer) was attached with an old conductor on the upper half of the breaker. This I presume was going to the dryer. The newer conductor attached to the lower part of the breaker appeared to be a #12 that was providing service to an exterior receptacle and light. When I tested the dryer receptacle, it did indicate 240 volt service. I am confused since it appeared that only one conductor was attached for the dryer (upper half of 30 amp breaker). Also, if not mistaken, the exterior receptacle and light should be attached to a 15 or 20 amp breaker not 30 amps. On a separate issue, should the white conductors on the 30 amp and 50 amp breakers in the Square D panel be wrapped with tape to indicate that they are now hot.

In regard to the Cutler Hammer sub panel, I am recommending that the panel be further evaluated since it appears to be outdated to today’s modern wiring requirements. Any comments on this panel would be appreciated.

By the way, go Broncos!

Both 30 amp breakers have oversized wire gauges which one looks like Aluminum stranded - older looking wire , and other has strands not even under the screws. Also the 50 amp looks like it has a wire gauge too small for breaker. That looks entirely wrong from here. Yes the neutral should have white tape to id it as neutral. Call out the entire panel for review prior to closing for estimate of cost for repair

Forgot to ask, i dont see a green screw in upper part of panel. Is there a bonding jumper in there at all. Where is the grounding electrode. Water pipe , ground rod?

The 2 pole-30 amp CB appears to be feeding the old subpanel with 120 volts. Yes, the white conductors should be re-identified as ungrounded conductors. The receptacle and light should not be on a 30 amp OCPD. I don’t see any aluminum conductors.

The foto of the up close right side 30 amp breaker with old cloth wire , if u can zoom in it , it looks like alum stranded wire not copper.

Never saw Aluminum wire with cloth covering saw lots of Tin covered Copper with Cloth /Rubber covering.

Yes good point , did they make tin covered copper in stranded? That’s good to know if they did , we concentrate so much on single strand - solid aluminum , just assumed the multi stranded type was aluminum. Probably is tin covered then.

A sharp knife and you can scratch the surface and see it is copper under the tin.
Yes they did make tin plated stranded copper and still do


The old wire is tinnned copper, not aluminum.

If this is the service then there are few things besides those already mentioned. There is no GEC connection and no main bonding jumper. Not sure how all of those cable enter through one KO in the top.

Also depending on what the 50 amp CB is feeding those conductors appear to be #8 which is only good for 40 amps if it’s NM cable.

You may wanna include trimming back the ivy 12" away from the structure as well .