2 New start relays tested bad(?)

[Pauli]

I ordered a new start relay (PTC) for a refrigerator and when I tested it with the ohmmeter  between terminals 2 and 5 I got no sound or reading, just OL. but got a good reading between the common on front and the L blade on back (less than 1).  On autorange M ohm setting, the next highest on my multimeter  after sound setting, it climbed  to 40 and then OL. It is the enclosed type with interior coil and I have read a number of places that a good one shows less than 100 ohms between 2 and 5 and usually just a few ohms. I tried the relay on the compressor anyway and it did not work....surprise. I ordered another one from a different place - exactly the same - and when I got it it tested the same - so I did not use it.  As far as I know it is the right part according to the look up tables for the model (Embraco 51306008/CLS30820101)- a replacement for the original part that was discontinued (Embraco 513604039). Correct hookup was verified also. And, I used another meter and got the same readings and tested another new one that is not for my refrigerator and it tested sound positive and showed  6 ohms or less.I did shake them lightly but no rattling although there is a very light sound of movement but not like loose pieces more like a springy sound and is the same for the good one. One thing I did notice though is that with the good one, which was considerably smaller, I got a reading much closer to the openings while the bad ones were a bit deeper - I do not know if this is a size-related thing or has any significance. This start relay is too expensive (around $100 or more especially with fast shipping) even if it did work and looks really cheaply made, but it still seems unlikely I would get two bad brand new relays from different vendors unless both were from a bad lot -but it seems to be the case or am I misunderstanding or missing something in my assessment?  Any thoughts and / or guidance would be appreciated.

[Hiroshi]

 

1 hour ago, Pauli said:

climbed  to 40 and then OL

That is how PTC start relays work, Pauli. They will only pass current for a split-second before their resistance goes to infinite, this is how the electrical current is routed to the run winding and away from the start winding, essentially, imitating what the old magnetic coil start relays used to do, but doing it with conductor material properties, not mechanically...

Did the compressor "hum" and then the thermal overlaod "click?"

Next thing I would do is Ohm test the compressor windings- take a reading from all three 2-pin combinations and two of the readings should add up to the highest reading (roughly)