Rockwell Automation 873C Ultrasonic Sensors - Manual

Installation Instructions
Bulletin 873C Ultrasonic Proximity Sensor
IMPORTANT: SAVE THESE INSTRUCTIONS FOR FUTURE USE.
!
CAUTION: Solid-state devices can be susceptible to radio frequency (RF) interference depending on the power and
the frequency of the transmitting source. If RF transmitting equipment is to be used in the vicinity of the
solid state devices, thorough testing should be performed to assure that transmitter operation is
restricted to a safe operating distance from the control equipment and its wiring.
!
WARNING: If a hazardous condition can result from unintended operation of this device, access to the sensing area
should be guarded.
Specifications
Switching Output Analog Output
New Part Number 873C-DDNP1000E2 873C-DDAV1000E2
Old Part Number 873C-D30NP30-E2 873C-D30AP30-E2
Nominal Sensing Distance 30cm (11.8 in.) to 1m (39.4 in.)
Output Configuration N.O., PNP Analog, PNP
Operating Voltage 18-30V DC
Load Current ≤ 400mA ≤ 5mA
Minimum Load Current 1mA
Leakage Current ≤ 10 µ A
Voltage Drop ≤ 2.4V
Repeatability ± 5mm in axial direction
Hysteresis ≤ 15mm typical
Ultrasonic Frequency 200kHz
Max. Switching Frequency 5Hz
Ultrasonic Pulse Cone Angle 8 ° (full angle)
False Pulse Protection Incorporated
Transient Noise Protection Incorporated
Reverse Polarity Protection Incorporated
Short Circuit Protection Incorporated
Overload Protection Incorporated
Enclosure NEMA 12 and IP65 (IEC 529)
NickelĆplated brass barrel
Connection Cable: 2Ćmeter (6.5 ft.) length
3Ćconductor PVC
LED Output Energized
Operating Temperature -10 ° C to +60 ° C (-14 ° F to +140 ° F)
Shock and Vibration 30G, 10-55Hz
Analog Output Voltage vs. Target Distance
(Background Suppression at Maximum Distance)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1
2
3
4
5
6
7
8
9
10
Sensing Distance (meters)
Ouput Voltage (V
DC)
Background
Suppression
Setpoint
(Adjustable)
Description
Bulletin 873C ultrasonic sensors are solid-state devices
designed for noncontact sensing of solid and liquid objects.
The normally open switching (discrete) model features a long
sensing range which can be adjusted between 30cm (11.8in)
and 1m (3.3ft). All sound-reflecting objects that are within the
selected sensing range and more than 30cm from the sensor
face can be detected.
The analog model provides an output voltage that varies
linearly with target distance. For many applications, such as
monitoring the level of water in a tank or accurately positioning
a cardboard box, this technology allows a single device to do
a job that would otherwise require multiple sensors.
Each unit is housed by a plastic face and a nickel-plated brass
barrel which meet NEMA 12 and IP65 (IEC 529) enclosure
standards. It is equipped with a 2m (6.6ft) PVC cable and an
LED which glows when a target is detected.
Theory of Operation
Ultrasonic sensors emit bursts of high-frequency sound waves
which reflect or “echo” from a target. When the device detects
an echo, it energizes the load. This allows these sensors to
detect an object of any shape and material that can sufficiently
reflect an ultrasonic pulse.
Each switch senses the distance from its face to the target by
measuring the length of time required for the echo to return.
The analog model converts the time value to a DC output
voltage. The discrete model compares this time to a pre-set
value (set by the user at installation) and energizes the load
when the time drops below the threshold.
Sensing Distance
The 873C is designed to detect objects which are between
30cm (11.8in) and 1m (39.4in) from the sensor face. The
discrete switching model’s maximum sensing distance can be
adjusted within this range by turning the potentiometer on the
end of the sensor.
Any objects in front of the sensor must be at least 30cm from
the detector face. Objects closer than 30cm will not be
detected and will block the sound waves coming from the
sensor.