At present, a power-on triggering manner is used for triggering a latch hook of a steel rope brake used in an elevator. However, the power-on triggering control manner has a disadvantage that a triggering device is unable to trigger a switch (latch hook) mechanism of a brake in case that external power is lost, a back up supply is insufficient, or a circuit or device goes wrong, and thus it has a high safety risk degree. Specifically speaking, a power-on triggering manner has long safety chains along vertical and horizontal directions. In the vertical direction, a safety chain formed by a power supply, a control logic unit, an electromagnet, a back-up power supply and a triggering device. In the horizontal direction, in a power-on triggering process, failure detecting and monitoring links are more, and it is relatively difficult to implement failure-free monitoring feedback, where a brake is unable to pick up as long as one link goes wrong because this may cause a fatal risk that a switch (locking) mechanism is failed in turning on; meanwhile, the power-on triggering is larger in sustained current, and larger in capacity required for a back-up power supply, slow in system response, and high in power consumption.