I'm not proud so feel free to laugh at my ignorance ...

I need to close (or open) a switch upon the application or removal of a dc signal. If possible, I need to accommodate a wide range of voltages in the trigger signal 3.3 - 24v and an equally wide range of currents (from a few milliamps to 1 amp).

If the trigger signal was constant, I'd use a transistor or ss relay (I can put 3v over the target switch if needed) but have no idea how to do this for an unknown signal. A reed relay?

Thanks in advance

 

Where is this signal coming from?

You can use a comparator IC supplied by 24V DC and when the input voltage is above 3.3V it will control a relay (if its output current rating allows) or something.

 

do you have a schematic diagram for this? You can try using a mosfet with a high current rating and a Vgs => 3.3V

 

this is a general purpose input - it could be anything from an analog sensor 4-20ma (converted to 0v or voltage) to the electrical system of a piece of equipment. It may be impractical to do this but I'd like to covert 0v and any voltage at any current to a binary value by opening or closing a switch.

 

This description makes it even less likely that anyone can guess what you need.

 

If you want to convert a 0 to a 1, use an inverter, or Schmitt trigger.

I am taking a guess here, but Im guessing the thing sending the signal is usually outputting 0v and when it outputs something other than 0v you want to operate a switch?

Will a relay do?

a LOT more info on your part would be helpful.