I am putting an automatic backup system together to power a small cooling pump for thermal solar panels when the grid goes down. The pump moves glycol in the panels to heat exchangers in the basement and the thermal energy is stored in insulated tanks. When the power fails, the glycol quickly reaches 400 degreesF and is ruined- and lost through pressure relief. I’m using a RIB2401D relay to switch between the grid and an inverter. The 2401D is great for disconnecting from the grid but when it comes to bringing the inverter on line, it’s too fast. I need a delay in the relay that brings the inverter on line and it needs to do it’s switching well after the power goes off. The delay will eliminate the possibility of two ac sources being in the same place at the same time and will give the small computer running the pump a chance to consume any voltage inside itself so that when it powers back on with the inverter, it does a normal boot-up. I have both 120vac and 24vac available for powering coil relays. I thought that a capacitor would be able to do the job but don’t know how to go about setting that up. I don’t have any background in electronics and thought this would be the best place to find some help.