BACO Controls · L21 Series

L21AE03

Active
CE

BACO 22mm Green Illuminated 24V 1NO

BACO Controls L21 Series Introduced circa 2000

BACO L21 illuminated green.

Common Applications

Budget German illuminated start button.

Specifications

Certifications
CE
Color
Green
Contact Configuration
1NO
Cutout Diameter
22mm
Illumination
Illuminated
LED Voltage
24V

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 11 12 NO (open) 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.

Where to Buy

Price range

$1.38 — $34.12

across 2 distributors

Quick Specs

Certifications
CE
Color
Green
Contact Configuration
1NO
Cutout Diameter
22mm
Illumination
Illuminated

What People Are Saying

+

“Budget German illuminated start button.”

Reddit r/PLC 31 upvotes View thread →