Frequently asked questions and answers for Push Buttons, Indicator Lamps - Industrial Automation
Question
What are the terminal symbols?
Answer
1. C or COM: Common terminal
2. NC: Normally closed terminal
3. NO: Normally open terminal
4. Lamp terminal (If DC polarity is required, it is indicated by + and -)
Question
Must a limiting resistor be connected to the LED of the lighting part?
Answer
The following models are not provided with a limiting resistor and so it is necessary to connect an external resistor.
Pushbutton Switches "A3D", "M2D", "A3A"
The following models provided with a limiting resistor do not require an external resistor.
Pushbutton Switches "A16" (M16), "A22" (M22), "A3P" (M2P), "A3K" (M2K), "A3S" (M2S)
Question
What is the Socket Unit?
Answer
The Socket Unit is the unit that opens and closes the electrical circuit.
Socket Unit
What is IP-[][]?
AnswerDegree of Protection
Note:IP-[][] degrees of protection given in this document were confirmed by OMRON based on the test conditions given below. Confirm satisfactory sealing performance in the actual operating environment and under the actual operating conditions before use.
IEC (International Electrotechnical Commission) Standards (IEC 60529 2001)
First symbol: Degree of protection against solid materials
Second symbol: Degree of protection against water
IP69K is a standard for protection again ingress of high-temperature, high-pressure water defined in the German standard DIN 40050 Part 9. The test piece is sprayed with water at 80° at 80 to 100 bars with a nozzle of the specified shape. The water volume is 14 to 16 l/min. The test piece is separated from the nozzle by 10 to 15 cm and water is sprayed for 30 s each at 0°, 30°, 60°, and 90° while the test piece is rotated on a horizontal plane.
*1.OMRON Test Methods
The Proximity Sensor’s IP67 degree of protection was confirmed by performing the tests described in the table below and making sure that the sensing distance and installation resistance satisfied the performance specifications after repeating a heat shock cycle 5 times, consisting of immersing the Sensor in cold water at 0°C for 1 hour followed by hot water at 70°C for 1 hour.
*2.Precautions on OMRON Testing
Operating conditions for E2F Proximity Sensors: Underwater within 10 m
(1)No penetration of water when immersed in water for 1 hour at an atmospheric pressure of 2
(2)Satisfies sensing distance and insulation resistance performance specifications after the heat shock cycle described in *1 is repeated 20 times
In-house Standards for Oil Resistance
Note:Oil resistance is confirmed using oils and cutting oils stipulated by OMRON (equivalent to previous JEM standards).
What is LED lighting?
An LED is mounted on the base plate of the Operating Unit. It is built in and cannot be removed from the Operating Unit.
What is the degree of protection for A22Z-B101/A22Z-B201 Control Boxes for A22 Push Buttons?
The degree of protection is IP65 if you use Control Boxes as a set with A22Z-3500-1 or A22Z-3500-2 Connector type Push Buttons.
If there is a lot of dust, it is recommended to also use A22Z-3600F Sealing Caps (for flat models), A22Z-3600T Sealing Caps (for projection models), or A22Z-3600G Sealing Caps (for full-guard models).
What is "momentary action"?
A momentary action is the action where once a switch has been operated and the button released, the switch returns to its initial status.
How do you calculate the control resistance for A3D/M2D Push Buttons LED lamps?
Set the control resistance within the range for the LED lamp characteristics.
(Set the forward current for the LED lamp to 8 mA min.)
Use the following formula to find the external resistance.
Control Resistance (Recommended Values)
Calculation Example: A3D
LED lamp illuminating color: Red
E = 24V
IF = 20mA
Ta = 25℃
Based on the VF-IF characteristics in the diagram below (red):
VF = 1.7 V when IF = 20 mA.
Therefore, inserting the values into the formula above (R = E - VF/IF(Ω)):
R = (24 (V) - 1.7 (V))/0.02 (A) 1100 (Ω).
The recommended resistance is 1.1 kΩ at 1 W (2 x IF2R).
Note:Approximately twice this value is appropriate to provide a margin in the capacity of the resistor.
A3D Series
A3A Series
A3D Series
Applicable models: A3D Push Buttons, A3A Push Buttons, etc.
What is an alternate action?
The push-push alternate switch action makes the contact remain ON with the first push action, using a mechanical lock mechanism inside the device. The second push action releases the lock and returns the contact to OFF.
The push action makes the contact remain ON using an internal mechanical lock mechanism. The pull action releases the lock and returns the contact to OFF status.
The lamp does not light up even when Illuminating Type Push Button Switches are pushed.
Check the following points.
1. Is the polarity of the lamp is connected correctly?
2. Are the lamp's voltage specifications compatible with the applied voltage?
3. Terminals of the LED and the switch are separated and so it is necessary to connect them.
The terminal layout of the A16 is as follows.
Does OMRON engrave or print the Legend Plates?
No, OMRON does not engrave or print Legend Plates.
Please find a printing company to do the work.
How much inrush current do a pushbuttons lamp have?
There is an inrush current of about 10 times the normal operating current for incandescent lamps. LED lamps and neon lamps do not have inrush current.
Is a blue LED lamp available for A3C Push Buttons and M2C Indicator Lamps?
There is a blue LED lamp for A16 Series Push Buttons and M16 Series Indicator Lamps and it can also be used for the A3C and M2C.
Example: For 24 VDC, A16-24DA would be used.
What is the difference between illumination only and colored illumination?
With illumination only, the color of the operating surface and the LED are the same. With colored illumination, the operating surface is white and a different colored LED is lit to emit color.
For example, if a red LED is used with illumination only, the switch will be red both when lit and not lit. With colored illumination, however, the operating surface will be white when not lit and will be red when lit.
The following diagram shows the A16 component configuration.
Example: Red Illumination
Example: Red Illumination
What part should I replace to change the 24-VDC voltage of the lamp for A16L-[]-24D Push Buttons to 12 VDC?
The Socket Units can be used for both voltages. Simply replace the LED lamp. The model is A16-12DS[]. (Insert the color symbol in the box.) R: red, G: green, Y: yellow, W: white: A: blue. For blue, however, the suffix is -12DA.
What is LED lamp illumination?
LED lamp illumination uses an LED with the same shape as an incandescent light bulb.
The LED can be replaced because the LED lamp and the operating section are separate.
Are the A3G/A3B Push Buttons and A16 Push Buttons compatible?
The Switch Guards, Dust Covers, and Hole Plugs are compatible. (The model numbers have been changed to models for A16.)
The Cases, Socket Units, and Operation Units are not compatible.
Can I use the incandescent lamp or LED lamp that I used with A3G/A3B Push Buttons also with A16 Push Buttons?
Yes, you can. As of July 2001, the LED lamp for A16 has been changed to a high-intensity LED. The intensity is different from the previous LED.
What can be the cause and what are the possible countermeasures if the M2BJ-B[][] pushbuttons AC/DC shared buzzer does not sound?
There is a smoothing capacitor in the internal circuit and it is possible that inrush current has caused the switching power supply to overload, resulting in no outputs.
Possible Countermeasures
1. If there is a switching power supply overload, it is possible to reduce the inrush current by connecting an external limiting resistor (20 to 30 Ω) in series.
2. The M2BJ-B[][]-D for DC only has no inrush current.
Can the contact configuration for A22K Key-type Selector Switch be changed to DPST-NO + DPST-NC or 4PST-NC?
Yes.
Add two Switching Units to the switch section.
The following table lists the combinations with Switching Units that can be used.
What is the Operation Unit of Push Buttons?
The Operation Unit is a unit that transmits an external operation or movement to the Switch.
A16 Series Push Buttons Example:
Can the Push Button Switches be used with the minimum load current?
Yes. Some of the Pushbutton Switches can be used.
1. Applicable models (minimum application load)
1) Pushbutton Switch "A16 Series": DC5V1mA
(exception: A165E-[]-[]-01/02: DC5V160mA)
2) All A3D Series: DC5V1mA
3) All A3C Series: DC5V1mA
4) A22 Switch Unit for minimum load: DC5V1mA
5) A3P Minimum Load Series: C5V1mA
6) A3K Minimum Load Series: DC5V1mA
If a switch for common load is used for minimum load switching, loose connection may be aused. Refer to the following diagram and use the switch within the area of use.
In addition, even when a minimum load type switch is used in its area of use shown in the following diagram, if a load generating incoming currents when switching is applied, insert a contact protection circuit if required.
Otherwise, it may cause contact erosion and then decrease in working life.
What are Enable Switches (Enabling Components)?
They are used in a variety of systems such as a teaching box of robots. When we sense danger, we can stop the control system in robots by strongly pressing and leasing the enable switch to ensure our safety.
Are there water-resistant pushbuttons?
A165/A22 Series Pushbuttons has drip-proof with IP65 protection.
Only the front of the panel is drip proof, however. The rear panel is not.
What is incandescent illumination?
Incandescent illumination is a lighting method using incandescent light bulbs. The incandescent light bulb and the operation unit are separate and independent.
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