Schneider Electric · Harmony XB4 Series

ZB4-BL3

Active
UL CSA CE

22mm Green Extended Push Button

Part number: ZB4 - B - L - 3
Schneider Electric Harmony XB4 Series Introduced circa 2003

Schneider Harmony XB4 green extended round push button.

Common Applications

Extended (protruding) button for easy access. Used where operators need to press without looking — conveyor start stations positioned at arm height, machine tool cycle start. The raised profile makes it findable by touch.

Specifications

Actuator Function
Momentary
Actuator Shape
Round
Actuator Type
Extended
Certifications
UL, CSA, CE
Color
Green
Cutout Diameter
22mm
IP Rating
IP66
Material
Metal

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

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

$47.5 — $53.47

across 2 distributors

Quick Specs

Actuator Function
Momentary
Actuator Shape
Round
Actuator Type
Extended
Certifications
UL, CSA, CE
Color
Green

What People Are Saying

+

“Schneider Electric ZB4-BL3 is a solid choice for push button applications. Standard specs, well-supported.”

Reddit r/PLC 18 upvotes View thread →