Test circuit, detection device and method for detecting electronic switch board

The embodiment of the invention provides a test circuit, a detection device and a method for detecting an electronic switch board. The test circuit comprises a voltage transformation and rectificationdevice, a current limiting device, a relay, an indication device, a test switch group and a plug-in assembly used for being connected with a switch board to be tested. The first test end of the plug-in assembly is used for providing a reference signal for the switch board to be tested. The output end of the voltage transformation and rectification device is connected with the current limiting device. The current limiting device is connected with the second test end of the plug-in assembly. The output end of the voltage transformation and rectification device is also connected with a coil of arelay, the coil of the relay is connected with a test switch group, the test switch group is connected with a third test end of the plug-in assembly, and the second test end and the third test end are respectively used for pr