What controller are you using for this purpose?
You can have this:
A non-inverting amplifier with a gain of +10 (or adjusted as required) has its input connected to the voltage source. The output has a zener diode to clamp the voltage.
A voltage-divider to step down the +25V down to the required range (eg. max +5V).
These are both connected to the controller/ADC. The controller decides when to read from which input.
This, I think, is a simple method. However, it will either require a lot of ADC channels, or another interfacing circuit which the controller controls to connect the output of one of these stages to the controller input.
Hope this helps.
Tahmid.