new for plc

hi,
i am new for plc. i want to do program with NAIS(FP-e) control unit.
it is a 8 i/p and 60 o/p.i want to do programming for my system
working in some temprature range.it's like 20F to 40F.if system
goes beyond or below this range my whole system is shutdown.
anybody have solution of my question please write me.lots of thanks.

thanks

balu

You need to have an analog signal for the temperaure. You then need to use a comparison function (>, <, ¨n, etc) to set an internal coil to flag the operations you require.

An alternative!

Since you are only concerned with the temp. 'going beyond or below' the given temperature range. You can do well with two thermistor circuits, to check just for this condition. This way your PLC need not be the one that supports analog inputs.
If you design the 'temp. sensing ciccuit' carefully you can do with just one input. But, that's not a concern I believe.