Will the cable below work on a 150 ft run if I double the power cables? (Single cable for the sensors, and doubled cables for power) the cables will be run on top of the ground for now. There's no amp or volt rating listed except for 'low voltage'.
I just took a chance on a 'New' DiSEqC box on Ebay that someone supposedly has never removed from the box. $35 with free shipping. If it's good, mama's gonna move up to a motorized bud. (If it's bad...well...let's just say she will never know about it.

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18/2 Gauge AWG 500ft Alarm Security Wire Cable Stranded Conductor Shielded
Brand New High Quality Alarm Cable 500FT. This high quality wire is used for all alarm sensor connections or for other low voltage applications. Use it to connect door and window sensors, motion detectors, keypads as well as other hardwired accessories to your alarm panels. Ideal for Indoor Remote Control of security, Intercom, and Sound Systems. Flexible PVC outer jacket with Rip cord. Can also be used for Powering Limited-Control Circuits or Burglar Alarms.
1 x 18 AWG, 2 stranded shielded conductors.
Easy-pull box.
Color: White.
Thanks in advance for any advice!