Rockwell Automation 875 User Manual

INSTALLATION INSTRUCTIONS

BULLETIN 875C, 875CP, 875L CAPACITIVE PROXIMITY SENSOR

IMPORTANT: SAVE THESE INSTRUCTIONS FOR FUTURE USE.

ATTENTION: 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.

ATTENTION: If a hazardous condition can result from unintended operation of this device, access to the sensing

area should be guarded.

Part Number Configuration

875 CP – D M 30 N P 34 – A 2

Capacitive

Proximity

Sensor

C = Cylindrical metal body (shielded)

CP = Cylindrical plastic body (unshielded)

L = Limit switch style

Nominal sensing distance (in mm)

2, 5, or 10mm = shielded construction

4, 8, 20, or 30mm = unshielded construction

A=AC

D=DC

M = Smooth barrel

Specifications—AC Models

Max. Load Current 300mA

Inrush Current 2A

Leakage Current 3.5mA

Operating Voltage 20-250V

Voltage Drop <10V

Repeatability

Hysteresis

Max. Switching Frequency 15Hz

Transient Noise Protection Incorporated

Enclosure NEMA 12, IP65 (IEC 529)

Approval CE marked

Connections Cable 2Ćmeter length

Operating Temperature

Allen-Bradley capacitive sensors are manufactured and tested to the international standard IEC 947–5–2.

≤10% ≤20%

Plastic or nickel-plated brass

2Ćconductor PVC

QuickĆDisconnect 3Ćpin micro

LEDs Green: Power

Yellow: Output

-25°C to +70°C (-13°F to +158°F)

P = PNP

N = NPN

E = Selectable

N = Normally open

C = Normally closed

E = Selectable

Specifications—DC Models

Max. Load Current 12, 18mm

Leakage Current 12mm

Operating Voltage 12mm

Voltage Drop 12, 18mm

Repeatability

Hysteresis

Max. Switching Frequency 12, 18, 30, 34mm

Transient Noise Protection Incorporated

Reverse Polarity Protection Incorporated

Short Circuit Protection Incorporated

Overload Protection Incorporated

Enclosure NEMA 12, IP65 (IEC 529)

Approval CE marked

Connections Cable 2Ćmeter length

LEDs Green: Power

Operating Temperature

Housing diameter (mm) (cylindrical types)

Head width (mm) (limit switch style types)

A = PVC cable

D = DC micro connector

P = Pico connector

R = AC micro connector

T = Terminal chamber

30, 34mm, limit switch style

18, 30, 34mm, limit switch style

30, 34mm, limit switch style

≤10% ≤20%

limit switch style

Plastic or nickelĆplated brass

3Ćconductor PVC

Quick-Disconnect 4Ćpin micro

3Ćpin pico

Conduit Opening 1/2Ć14 NPT internal

thread with screw terminals

Yellow: Output

-25°C to +70°C (-13°F to +158°F)

Cable length (m)

Number of pins

Number of terminals

200mA 400mA

0.3mA

0.1mA

10-36V 10-60V

<2V <3V

25Hz 40Hz

Wiring

All external wiring should conform to the National Electric Code and applicable local codes. Connect the proximity switch to the power supply and load as shown in the wiring diagrams below. If the positive (+) and negative (–) wires are reversed, the switch will not operate properly . The sensor will not be damaged because it is equipped with reverse polarity protection.

Wiring Diagrams for AC Switches

Cable Micro-Connector

Normally Open or Normally Closed

Black

Blue

Load

Note: Load can be switched to black wire.

Note: Load can be switched to pin 2.

Load

Wiring Diagrams for DC Switches

Cable

Normally Open or Normally Closed

NPN (Sinking)

10-36V DC (12mm) 10-60V DC (18-34mm)

Brown

Load

Black

Blue

+ -

Micro-Connector

Normally Open or Normally Closed

NPN (Sinking)

21 34

Load

10-60V DC

Pico-Connector

Normally Open or Normally Closed

NPN (Sinking)

Load

10-36V DC (12mm) 10-60V DC (18mm)

Terminal Chamber

Normally Open or Normally Closed

NPN (Sinking) PNP (Sourcing)

10-60V DC

Load

+ -

PNP (Sourcing)

10-36V DC (12mm) 10-60V DC (18-34mm)

Brown

PNP (Sourcing)

-+ Load

PNP (Sourcing)

10-36V DC (12mm) 10-60V DC (18mm)

10-60V DC

Black

Blue

21 34

10-60V DC

Load

Wiring Switches in Series

Switches can be connected in series with a load. For proper operation, the voltage across the energized load must be less than or equal to the minimum supply voltage minus the voltage drops across all sensors. The load will be energized only when all switches are closed.

Wiring Switches in Parallel

Switches can be connected in parallel to energize a load. The sum of the maximum leakage currents for the switches must be less than the maximum off-state current of the load device. The load will be energized when one or more of the switches are closed.

Sensing Distance Adjustment

The sensing distance of an Allen-Bradley capacitive proximity sensor can be adjusted via a twenty-turn potentiometer at the rear of the sensor housing. Although this is a clutched potentiometer, it does not emit an audible “click” when turned beyond its range.

The maximum sensing distance for each sensor can be determined using the part number configurator on page one. If the sensing distance is set higher than the maximum, the unit may lock in the triggered state. The minimum distance to which each sensor can be adjusted is listed in the table below. Nominal sensing distances are measured using a standard target (see Target Considerations).

Minimum Adjusted Sensing Distances

12mm metal housing: 0.4mm 18mm metal housing: 1.0mm 18mm plastic housing: 2.0mm 30mm metal housing: 2.0mm 30mm plastic housing: 5.0mm 34mm plastic housing: 7.0mm limit switch style housing: 10.0mm

This unit is not designed for reliable operation when adjusted to distances shorter than those stated above.

Adjustment Procedure:

1. Mount the sensor on a stable surface or support (see Mounting Considerations).

2. Apply power to the sensor per wiring diagrams (see Wiring). Check that the green “power” LED turns on.

3. Determine a desired sensor-to-target distance which is between the unit’s rated minimum and maximum sensing distances (see Target Considerations and Dielectric Constants).

4. Multiply this desired sensing distance by 1.2 and place the target at the resulting new distance from the sensor. Check the yellow “output” LED status.

5A.(Normally Open Models Only) If the yellow LED is off, turn

the potentiometer slowly clockwise until the LED turns on. If the yellow LED is already on, turn the potentiometer counterclockwise until the LED turns off, then slowly clockwise until the LED turns on again.

5B.(Normally Closed Models Only) If the yellow LED is on,

turn the potentiometer slowly clockwise until the LED turns off. If the yellow LED is already off, turn the potentiometer counterclockwise until the LED turns on, then slowly clockwise until the LED turns off again.

6. Remove the target and check that the yellow LED turns off for normally open models and on for normally closed models.

7. Place the target at the original desired sensor-to-target distance determined in step 3. If the yellow LED turns on for normally open models and off for normally closed models, the sensor is correctly adjusted.

+ 2 hidden pages