The carrying capacity of intrinsic safety power supply is tested, and it is found that the carrying capacity is poor. After analysis, it is found that the maximum load capacitance of 18V / 1A intrinsically safe power supply is only 2.2u F, and the capacitance of the connected equipment is far more than 2.2u F, which leads to the power supply entering the protection state. Therefore, the 10u f capacitance used for power filter on the board is replaced by 1U f capacitance, and the effect is improved, but it is still not ideal. Consult the description of intrinsically safe power supply and consult the technical personnel of the power supply manufacturer. The technical personnel suggest that the cut-off intrinsically safe power supply should be replaced with the limited current intrinsically safe power supply, so the MKD intrinsically safe power supply should be replaced with the mkda intrinsically safe power supply with strong carrying capacity, and then tested. One intrinsically safe power source can be equipped with two loudspeakers with emergency stop, four emergency stops and one terminal, with a distance of 400m Left and right, basically meet the requirements of carrying capacity.