Schneider Electric · Harmony XB4 Series

ZB4-BG1

Active
UL CSA CE

Harmony XB4 2-Position Key Switch

Part number: ZB4 - B - G
Schneider Electric Harmony XB4 Series Introduced circa 2003
Schneider Electric ZB4-BG1 — Harmony XB4 2-Position Key Switch

2-position key-operated selector switch head for Schneider Harmony XB4 series. 22mm cutout, IP66. Key removable in both positions.

Common Applications

Key-operated selector switch used to restrict access to specific machine modes — only personnel with the key can switch between positions. Common on pharmaceutical filling lines (locking out manual mode during production), food processing equipment (preventing unauthorized recipe changes), and building HVAC panels (restricting access to maintenance mode). The maintained 2-position action stays in the selected position when the key is removed from either position. Pairs with ZB4-BZ101 or ZB4-BZ102 contact blocks depending on whether the application needs NO or NC contacts.

Specifications

Actuator Type
Key
Certifications
UL, CSA, CE
Contact Configuration
1NO (with ZB4-BZ101)
Cutout Diameter
22mm
IP Rating
IP66
Material
Metal
Mounting Type
Panel
Max Operating Temp
70°C
Min Operating Temp
-25°C
Positions
2
Return type
Maintained

Installation Quick Reference

Panel cutout: 22mm. Align the selector positions with the desired panel markings before tightening.

Contact blocks: Attach one contact block per position. Wire each to a separate PLC input for position feedback. A 2-position switch needs 1-2 blocks; 3-position needs 2-3.

Wiring Diagram

L T 11 12 NO (open) press ↓

Troubleshooting

Not responding to input

Check wiring continuity with a multimeter. Verify the contact block is properly seated. Inspect terminals for loose connections.

Quick Specs

Actuator Type
Key
Certifications
UL, CSA, CE
Contact Configuration
1NO (with ZB4-BZ101)
Cutout Diameter
22mm
IP Rating
IP66