| 摘要 |
The supply network uses an electromagnet load relay (4) for 3 network phrases, operated by a push-button closure contact and incorporating a self-holding circuit. The relay coil is coupled in circuit with the closure contact (30) of a second electromagnetic relay (28), the coil of which is coupled in circuit with a LV source (32) Each plug socket (6) incorpurates a switch which is closed upon insertion of a respective plug pin. The second relay is operated upon removal of the latter, to open the coil circuit of the load relay (4). |
