need help with trigger circuit

I need a circuit that will stay at a logic state low for ten or so minutes then switch and stay at a logic state high. I need it for a heater indicator to let you know the heating element is hot enough. Any and all help will be greatly appreciated.

Timing is no good advise if temperature is an issue.

To help you any further the temperature to monitor must be known to select an appropriate sensor..

Boncuk

listen to BONCUK's advise
your life and/or property may depend on it

Never fool around with electricity.
Not enough data is revealed to get a proper answer.

I'm running a piece of nichrome ribbon (resistance unknown) with a 12v 6A supply and controlling the temperature with a SSH7N90A mosfet. The temperature range will be between 310-400 deg. farenheit. I was going to use the timer as an indicator so it would light up when the element was hot enough, but I'd rather have a thermometer. If I used a temperature sensative resistor (thermistor i believe) and an op amp with an analog meter could I make a cheap analog thermometer? Any other ideas?

My goal is to be able to send a clock pulse from a 4001 NOR gate oscillator and increase the temperature by increments of 10 degrees.