| 摘要 |
The circuit connections are made in such a way, that with the operation of one of the relays a voltage of reversed polarity is supplied to the DC motor compared to that supplied with the operation of the other relay, and in the rest position of the first and second relays (6,7) no voltage is supplied to the DC pump motor (3). A pair of contacts (8) of a third relay (9) is arranged in series with the DC motor (3), and the third relay (9) is controllable together with the first and second relays (6,7), in such a way, that the pair of contacts (8) of the third relay (9) is open, if the first and second relays are in the rest position, and is closed, if either the first or the second relay is in a working position. The pair of contacts of the third relay includes one working contact. A protection diode (14) is connected in parallel to the DC motor (3. USE/ADVANTAGE - Reversible DC motor driving pump. Prevents higher braking current so that rest contacts of relay are not overloaded and after switching off of relay motor is not overloaded or e.g. vehicle battery is not discharged. |
