DSC 632 hybrid system: Multiple contacts on one transmitter

["glevin" <mikengroups@xxxxxxxxx>]

I recently purchased a DSC 632 hybrid system and found that the
instructions for the WLS925L-433 door/window transmitters say not to
put more than one contact on the external loop and "the wires
connecting the external device to the input terminals must not exceed
18 inches, provided that the resistance of the wire dies not exceed 100
Ohms."

I am replacing an old wireless system on which I had multiple
door/window contacts and about 40 feet of wire on one transmitter. I
measured the resistance of that normally-closed loop and got 18 Ohms. I
tested the transmitter often and it functioned flawlessly.

Why should there be a problem with multiple sensors on the external
loop of the DSC transmitter as long as the resistance is under the
specified 100-Ohm limit? Is DSC just trying to sell more transmitters,
or is there a better reason for the stated limitations? Parts of my
house are impractical to hard wire and I don't want to buy a separate
transmitter for each door and window if one transmitter can handle
multiple contacts.

I would appreciate any advice relating from folks with experience or
knowledge with this issue. Thanks in advance for your assistance.