Rockwell Automation 873M Ultrasonic Analog Sensors Installation Instructions - Manual (Page 2)

10000231110 Ver 03
873M-IN001A-EN-P
June 2013
Power, Control and Information Solutions Headquarters
Americas: Rockwell Automation, 1201 South Second Street, Milwaukee, WI 53204-2496 USA, Tel: (1) 414.382.2000, Fax: (1) 414.382.4444
Europe/Middle East/Africa: Rockwell Automation NV, Pegasus Park, De Kleetlaan 12a, 1831 Diegem, Belgium, Tel: (32) 2 663 0600, Fax: (32) 2 663 0640
Asia Pacific: Rockwell Automation, Level 14, Core F, Cyberport 3, 100 Cyberport Road, Hong Kong, Tel: (852) 2887 4788, Fax: (852) 2508 1846
www.rockwel lautomation.com
Wiring Diagram
Analog Output Characteristics
• The analog output mode returns a 4…20 mA or 0…10V DC
signal proportional to the measured value.
• The upper and lower adjustment range can be scaled to
distance-fixed window, giving the user more flexibility.
• The sensor is taught using an easy four-step remote teach
process or an optional programming cord.
• Two output functions: rising ramp and falling ramp.
Overview of Sensing and Adjustment Ranges
• When the target is beyond the far limit, or if target is absent,
the output is identical to the status at the far limit.
1 (Brown)
2 (White)
3 (Blue)
4 (Black)
+10…30V DC *
Remote teach
0V DC
Analog output by cat. no.
* Analog Voltage models are 15…30V DC
For example, if the span window is set to 4 mA at 7.62 mm (3
in.), and 20 mA at 203.2 mm (8 in.), the output will be 20 mA
when the target is anywhere at or beyond 203.2 mm (8 in.), or if
no target is present.
• In the blind zone, the output status is unpredictable because
the sensor does not have time to settle after the pulse. It is
therefore unable to accurately “hear” or interpret an echo.
• The adjustment range is where programming limits can be
stored; the sensing range is where stable sensing is possible
(see “Specifications”).
• The following example for a 300 mm sensor demonstrates the
need for both adjustment and sensing ranges:
If the blind zone were 0…30 mm, and you set a sensing
window of 50…300 mm, the output would become random/
unpredictable if the target object moved even slightly closer to
the sensor than 30 mm.
By defining the sensing range (usable but non-adjustable area
between 30 mm and 50 mm), the output is guaranteed to be
stable if the target mistakenly moves closer than the 50 mm
adjustable limit. Once the target moves into the blind zone
(closer than 30 mm) the output status becomes random/
unpredictable.
Setting Measurement Range
Rising Ramp: current or voltage values rise as the distance from
the target to the sensor increases.
Follow the steps below in the order they appear.
1. Place the target at the lower set point limit.
2. Using the white wire, connect to 0V DC [–] or press A1 on the
optional programming cable.
3. Place the target at the upper set limit.
4. Using the white wire, connect to 10…30V DC [+] or press A2 on
the optional programming cable
Falling Ramp: current or voltage values fall as the distance from
the target to the sensor increases.
Follow the steps below in the order they appear.
1. Place the target at the lower set point limit.
2. Using the white wire, connect to 10…30V DC [+] or press A2 on
the optional programming cable.
3. Place the target at the upper set limit.
4. Using the white wire, connect to 0V DC [–] or press A1 on the
optional programming cable.
Target Position
4
20
Set point P2 Set point P1
Analog Current (mA)
Target Position
0
10
Set point P2 Set point P1
Analog
V
olta
g
e (V DC)
Target Position
4
20
Set point P1 Set point P2
Analog Current (mA)
Target Position
0
10
Set point P1 Set point P2
Analog
V
olta
g
e (V DC)