Motor current quick-break Bach circuit b composed of electromagnetic current relay

Medium and small-capacity high-voltage motors generally use current quick-break protection as the main protection for phase-to-phase short circuit. For
high-voltage motors that are not prone to overcurrent, current quick-break protection composed of electromagnetic type (such as DL-11 type) current relays is usually used; for high-voltage motors
that may generate overcurrent , induction type (GL type) overcurrent relays can be used The inverse time limit part of the current quick-break protection and over-current protection is used as over-current protection and acts on the signal. The over-current protection time limit is generally 15 to 20 seconds, and the quick-break part is used as phase-to-phase short circuit protection and acts on tripping. The circuit is shown in Figure 4-51.