Electronic keyfob reader distance limitation?

Does anyone know what's the maximum distance (if any) for the key readers in the building?  From the electronic panel to the key reader.  
We use keyfobs for the building.  Sometimes one or two doors key readers (out of 5 total) do not react to the keyfobs.  And that those that farthest away from the electronic panels inside the Telco room.   So my suspicious would be a distance limit but I would be completely wrong.
Any knowledge in this?  Thanks.
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☠ MASQ ☠Commented:
You've not give us much to go on here, there are lots of different fob versions from powered RF with a range of 50 ft or so (think opening your car door) to the more common unpowered (passive) RFID which needs to be touched or at least in much closer proximity to the sensor which depending on the technology used can be between a few inches and up to 15 feet.  If your pad has an audible confirmation beep then simply walk towards it with the fob and wait for the beep.  That's your range!
Tiras25Author Commented:
yes that's the keyfobs that you have to touch the reader or almost touch it.   but the distance ..i'm asking from the reader wierd to the main panel board.
☠ MASQ ☠Commented:
if your controller is hard wired the limitation is simply the standard Ethernet limit. So unless  it's more than 300 feet away (CAT5) the cable isn't the issue  (although of course network cables often don't take the most direct route from A-B (!))

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To prior comments, much depends on your reader/setup.
The mentioned 300 feet deal with Ethernet/ip communication.
The presumption is that the reader is networked, versus electrically connected to a panel  
The specific system commonly defines the distances ...
Tiras25Author Commented:
I'm almost sure the readers are networked.  but if electrically connected the distance limitation should be much longer right?
Commonly, each setup provides guidance dealing with type, range and suseptibility to interference.
If shielded, distances would be longer.
Tiras25Author Commented:
Got it.  Thanks bunch guys!
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