Capacitive NO/NC Selectable AC/DC Sensors0 pages

Capacitive NO/NC Selectable AC/DC Sensors
FEATURES
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DESCRIPTION
Capacitive sensors are used to detect metallic and non-metallic
objects (liquid, plastic, wooden materials and so on). These
capacitive sensors have a normally open or normally closed output
selector switch and operate on a wide voltage range, 20 - 250 V
AC/DC. This greatly reduces the need to keep multiple sensors in
stock.
Their housing consists of a cylindrical threaded metal or plastic
30 mm diameter case. They are dust and water tight as well as
shock and vibration resistant. All models feature LED indication of
the output status and short circuit protection up to 50V in DC.
A screw placed on the sensor allows regulation of the operating
distance. This sensitivity regulation is useful in applications, such as
detection of full containers and non-detection of empty containers.
A waterproof protective housing is available. This housing is
made of a non-toxic material (POM) and has a standard 1 1/2" GAS
threaded fitting for mounting into a container. This housing permits a
sensor to be rapidly removed for testing without the loss of material
and protects the sensor from abrasion. The use of the housing can
help to eliminate variation in the sensitivity of the sensor due to
deposits of material.
OPERATING PRINCIPLE
Capacitive proximity sensors use the variation of the parasitic
capacity that develops between the sensor and the object being
detected. When the object is at a preset distance from the sen-sitive
side of the sensor, an electronic circuit inside the sensor begins to
oscillate. The rise or fall of such oscillation is identified by a threshold
circuit that drives an amplifier for the operation of an external load.
AC/DC Capacitive
NO/NC output selector switch
AC/DC power supply
Sensing of metallic and non-metallic objects
Adjustable operating distance
Cylindrical threaded metal or plastic casing
Short circuit protection up to 50V in DC
LED indication of the output logic status
Cable and connector versions
Protective housing available for mounting into containers
Compliant to the EMC directive
RoHS Compliant
The operating distance of the sensor depends on the actuator
shape and size and is strictly linked to the nature of the material
(Table 1.).
Capacitive sensors
Metal
~ 1 x Sn
Water
~ 1 x Sn
Plastic
~ 0.5 x Sn
Glass
~ 0.5 x Sn
Wood
~ 0.4 x Sn
Table 1. Sensitivity with different materials. Sn = operating distance.
2 wire AC/DC NO/NC select advantages:
• Reduces stock
• Easier installation
• Not polarity sensitive
• Compatible with PLC units
• Separate power supply not required
2 wire AC/DC considerations:
• The min. current required for the load (Example: Switching of a
relay) is ≥ the min. switching current of the sensor.
• The leakage current is not sufficient to cause activation of high
impedance inputs and is low enough to release low consumption
relays.
• Attention is given to the “on state” voltage drop when there is a
low supply voltage.
MODEL
Output
NO/NC select
S5140
S5141
S5170
S5171
Function
Operating Distance mm
0 - 20
0 – 25
External Diameter
M30 x 1.5
Power Supply
20 - 250 V ac/dc
Max. Switching Current
500 mA
Min. Switching Current
10 mA
Leakage Current
≤ 2 mA
Voltage Drop (On State)
<6
Short Circuit Protection
Yes ( Up to 50V in dc)
Operating Frequency(max)
10 Hz
Case
Nickel Plated Brass
Plastic
Dimensions
Fig. 5 (cable)
Fig. 6 (connector)
Fig. 7 (cable)
Fig. 8 (connector)
Flush Mounting
Yes
No
Protection Degree
IP 65
Operating Temperature
-20 to +70° C
Output Connection
Cable PVC 3x0.50mm²
Connector Type C2 *
Cable PVC 3x0.50mm²
Connector Type C2 *
Protective housing Model #
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S5911
S5912
* Mating connector with screw terminals included
www.fargocontrols.com
732 389-3376
Fax 732 542-3553
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