This standard applies to JH1, JH2, JH5, JH6, JH9, JH10, JF5, JXB, TD, NJD, H, SAK, TK, TB, TC, B1, TZ1, JX2, JX5, JD0, UK series terminal blocks (below Referred to as "terminal block"), this terminal block is suitable for electrical lines with AC 50Hz (or 60Hz) 690V (660V) and below, DC 440V and below, for line-end connection in power and control circuits.