I use a pitail tester like this to test for polarity on two prong receptacles. Push one end in the small slot and ground the other end between my fingers.
I often find reversed polarity on these.
http://homesmsp.typepad.com/.a/6a00e550bbaeb38834010535cadeb6970b-320wi
I may not recommend replacing as Jeff pointed out but I do mention in my report the differences with the two receptacles and why it’s important to either replace a damaged 2 prong receptacle with a like receptacle or a GFCI instead but never with a 3 prong receptacle and why. I do run into a lot of homes on the older 2 wire systems and find that they have installed 3 prong receptacles in place of the 2 in some instances. At least that way I’ve educated the client on the different systems.
Bert
I agree and I have not seen two Prong outlets for sale for many years
I stand corrected. I misspoke. The term BX is interchangeable here with AC and all MC is often referred to as BX.
I also agree there is no reason to upgrade to grounded 3 prong unless appliances that require ground will be used in these outlets.
Simple neon pigtail testers can give false readings under certain conditions.
A better option is a wiggy that puts a small load on the circuit.
http://www.kleinconnection.com/KleinConnection/images/69115_icon.jpg
I just did an old home that a few two prong outlets. Some parts of the home had been upgraded. The two prongs were typically loose and not great shape so I tested all with a pigtail. They all have power but still recommend an upgrade just because of condition and maybe preventive measure. The other three prong outlets were tested also and had open grounds and neutrals. I am never satisfied with testing one outlet per room. This home still had inactive knob and tube in the attic. There was a room air conditioner plugged into a two prong outlet with a grounding adapter. Have seen these things get hot. Not a good idea in my mind.
I find a few Bad, that’s enough for me to recommend Replace or repair .
I also find many I can not get at behind a china cabinet or the bed .
No way do I even try moving things like that .an accident I can not afford .
My last Inspection had a huge amount of Irish Bleek .Some pieces worth over $1,000;00.
Hi I have a house with wiring 1960 I think the first Time romex came out but had no grounds Replaced with gfci and 3 prong rec when I check with volt meter I get 120 volts from hot to neutral and 55 volts from hot to metal box on all lighting and receptacle circuits