TBBQ5 series automatic transfer switch is an integrated dual-power transfer switch with the controller built inside the body. The product is suitable for distribution system of AC 50HZ, 400V and below, which is used to monitor the power supply circuit. When a deviation (undervoltage, overvoltage, loss of voltage, etc.) is monitored for one of the two power sources (common power supply and backup power supply or power generator), it automatically switches one or several load circuits from that power supply to the other power supply, which is widely used in power distribution systems for civil buildings, business, industry, computer centers, highways, fire protection, security, etc.