Many insurance companies advise 60 amp service to home not acceptabble. Oftentimes homeowner upgrades with 100amp breaker box but service still 60 amp.My company states if service unknown then round meter on round base with 1 1/2" diameter conduit is 60amp service and therefore not acceptable. However, underwriter (UW) indicates if conduit larger than 1 1/2" likely 100amp so then eligible .

Asked an electrician if 1 1/2" conduit with round on round always 60amp and he said "N0. If diameter of plug splicing wires together before descending to meter are approx thickness of little finger then 60 amp service. But, if plugs diameter of thumb than likely an older 100amp service." Home in question small frame ranch built 1954.

Can you corroborate, or offer guidelines, to help make service determination without going to expense of hiring an electrician?

Wilson, do you not have access to the inside of the home?

Let me confuse you more. A typical 100 amp service can use 3 #2 aluminum conductors, all in an 1-1/4" conduit.

So the 1.5 in conduit theory is misleading.

Then there is Service Entrance Cable, no conduit. Could be #2 but still have a 60 amp Main Breaker.


There are so many variables, there is no safe "rule or thumb" to be certain of a service entracne size without looking at the rating of the Main Service Disconnecting Means.

Appreciate your prompt reply!

Given reply this is probable moot but for what it's worth wires on either side of splice appear similar in diameter.

Yes, can access inside. If permit pulled and box indicates 100amp on the main then expect it's 100amp..

But, if moonlighting electrician, or friend, updated fuses, or older breaker box with ato 100amp box without permit and didn't update actual service the main will read 100amp.

If this being the case what do I look for?

Which splice? The aerial cable from utility to the service entrance conductors in conduit on the building?

Bad comparison, if so. Utility conductors are often reduced in size for various reason, or the wire size is small but the insulation is larger. In anycase, not a good visual to assume all is 100 Amp.

If the panel has been changed to 100 amp and the remaining service entrance equipment and conductors have not been changed, or suspected, or not sure, one cannot assume this equipment is actually 100 amp rated without confirming the actual size of conductors and without reading the manufacturers label of the meter socket, which most times is not on the outside.

Unfortunately, the only accurate method would be to have an electrician open the panel to confirm size of service entrance conductors, and open the meter to read the label. and confirm wire sizes there.

Here is where is gets even more sticky. Many utility companies do not allow the electrician to pull a meter, for any reason, so they would need to be on site.

I realize your looking for a quick fix to inspect a service, probably for an insurance inspection or risk assessment, done that been there, and there is none that I can comfortably pass onto you.

Thank you!