The utility model relates to a control circuit for SVG cooling fan, including the total inlet wire of AC380, circuit breaker QF, circuit breaker QF11, QF12, contactor KM11, contactor KM12, protection circuit RC1, cooling fan, electric fan heater, the total inlet wire of AC380V is divided into two the way through circuit breaker QF is qualified for the next round of competitions, supplies power for the electric fan heater through circuit breaker QF11 all the way, and another sweetgum fruit is crossed circuit breaker QF12 and is supplied power for cooling fan, circuit breaker QF11's A1 end, B1 end, C1 end and contactor KM11's three input contact connection, contactor KM11's three output contact passes through protection circuit RC1 and is connected with the electric fan heater, circuit breaker QF11's C1 termination contactor KM12 trigger the contact after, connector contact ware KM11's coil. The advantage is: do the interlocking through the contactor in two circuits, avoid fan and electric fan heater to start simultaneously, cause the energy extravagant, reach energy -conserving purpose, improve fan efficiency. Increase the converter in the SVG cooling fan return circuit, greatly reduced energy loss, practice thrift a large amount of charges of electricity for the user.