Omron · A22 Series

A22-FR-01M

Active
UL CSA CE

A22 Red Flush Push Button (1NC)

Part number: A22 - FR - 01M
Omron A22 Series Introduced circa 2000
Omron A22-FR-01M — A22 Red Flush Push Button (1NC)

Red flush momentary push button, Omron A22 series. 22mm cutout, IP65, with 1NC contact.

Common Applications

Red stop button from the Omron A22 series. Standard on Omron-controlled production lines in electronics manufacturing, food packaging, and semiconductor handling equipment. The 1NC contact breaks the circuit on press. In Japanese and Korean factories, Omron buttons are the default choice — if you are maintaining imported Japanese machinery, this is likely what you will find on the control panel.

Specifications

Actuator Shape
Round
Actuator Type
Flush
Certifications
UL, CSA, CE
Color
Red
Contact Configuration
1NC
Cutout Diameter
22mm
IP Rating
IP65
Material
Plastic
Mounting Type
Panel
Max Operating Temp
55°C
Min Operating Temp
-10°C

Specs with this icon are linked to the manufacturer's original source page

Installation Quick Reference

Panel cutout: 22mm. Insert from the front of the panel, secure with mounting nut from behind (tighten to 2-3 Nm).

Contact block: Snap or screw the contact block onto the rear of the button body. Ensure the contact block orientation matches the wiring diagram — NO terminals are usually marked.

Wiring: Use 0.5-2.5mm² stranded wire with ferrules. Tighten screw terminals to 0.8 Nm. Test the button function before energizing the circuit.

Dimensions

Front 22mm cutout panel hole diameter Side panel contact ~45mm depth

Wiring Diagram

L T 21 22 NC (closed) opens on press

Troubleshooting

Button doesn't respond when pressed

Check the contact block first — it's the most common failure point. Test continuity across the NO or NC terminals with a multimeter. If no click is felt, the return spring in the head may be broken.

Works intermittently

Contact block contacts are pitted or burned. Replace the contact block — don't try to file the contacts. Check if the rated cycle count has been exceeded.

Button feels mushy or doesn't click

The spring return mechanism in the button head is worn. Replace the head. The contact block can usually be reused if it tests OK.

Quick Specs

Actuator Shape
Round
Actuator Type
Flush
Certifications
UL, CSA, CE
Color
Red
Contact Configuration
1NC

What People Are Saying

+

“Solid button for panel builds. Omron A22 series is well-proven in the field. Standard 22mm mounting means easy replacement if needed.”

Reddit r/PLC 10 upvotes View thread →

Data Sources

Specifications and product data sourced from the following references.

A22-FR-01M via Omron

https://www.ia.omron.com/products/family/3482/

Accessed April 04, 2026

Source