"Probe must me defective. Send her to the repair ward!"
12 - 15 volts is too low, even for setting 1 - 3. 15 volts are just barely enough for setting 1.
Yes, you do lack power (voltage), your feelings are right.
Did you weld from another receptacle before? Are you on an extension cord now, or a different one? Can you check the voltage on the transformer's primary side under load?
if you could tell me the procedure i will do it! i am plugged straight into 13 amp socket, no extention lead. what do you mean by another receptacle? if i put photo up would you point out transformer's primary side point of testing? regards, stan