The DTK503C is an obsolete sensor use a DUS704 instead. 

• Multifunction fully programmable sensor
• All functions remotely programmable
• Ceiling flush mount

Sensors:

• Narrow Angle 360O Ceiling Mount PIR Motion Detector
• Narrow angle "doorway" sensor
• Detection range 3m diameter
• LED activation indicator
• Adjustable Pulse Count
• Adjustable Sensitivity
• Sensor: Dual element pyro-electric
• R.F.I. Immunity: >15V/m @ 10-1000MHz

PE Features:

• PE Cell for light measurement
• Dynamic range < 5 lux to > 5000 lux
• Automatic "Daylight Harvesting" mode

IR Features:

• Infra Red Remote Control Receiver
• Range > 6m
• LED activation indicator
• Can be used with DTK500 series Infra Red remotes or other learning IR Remote controls

Sizes:

• Dimensions: H 90mm x Dia. 70mm. Mounting hole 56mm Dia
• Packed weight 0.1kg