Check out RS Components.

you can design one for your goal. its not complex by using a microchip or simple using two or three 555 circuit to implement the function.

its cheaper.

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you are not really explaining how you are controlling right now, but, an easy way to do this would be to write some simple code in to the program ie:siemens s7, off delay, just build in a DB and use the S5t#XhXXmXXsXXXms, trigger and then PV.

'Tork` makes programable time switches.