Schneider Electric · Harmony XB4 Série

ZB4-BS844

Ativo
UL CSA CE IEC 60947-5-5

Harmony XB4 Red Mushroom Emergency Stop (Push-Pull)

Número de peça: ZB4 - B - S - 844
Schneider Electric Harmony XB4 Série Introduced circa 2003
Schneider Electric ZB4-BS844 — Harmony XB4 Red Mushroom Emergency Stop (Push-Pull)

Red 40mm mushroom head emergency stop push button, push-pull reset, for Schneider Harmony XB4 series. 22mm cutout, IP66.

Aplicações comuns

Emergency stop button found on CNC machines, hydraulic presses, industrial robots, and food processing lines. The 40mm mushroom head meets EN/ISO 13850 requirements — large enough to hit with a palm or forearm in a panic. Twist-to-release prevents accidental restart after an emergency — the operator must deliberately acknowledge the event before the machine can run again. Required by OSHA and EU Machinery Directive on any equipment with moving parts that could injure an operator.

Especificações

Actuator Type
Mushroom Head
Certifications
UL, CSA, CE, IEC 60947-5-5
Color
Red
Contact Configuration
1NC (with ZB4-BZ102)
Cutout Diameter
22mm
Head diameter
40mm
IP Rating
IP66
Material
Metal
Mounting Type
Panel
Reset type
Push-Pull

Especificações com este ícone estão vinculadas à página fonte original do fabricante

Você também vai precisar de

Este é um componente modular. Para uma montagem completa, você também pode precisar de:

Referência rápida de instalação

Panel cutout: 22mm. Mount with the yellow backing plate visible (required by EN/ISO 13850).

Wiring: Wire NC contacts in series with the safety relay input channels. Use dual-channel wiring for SIL 3 / PLe applications. Never wire directly to a motor contactor.

Testing: Press the e-stop and verify the machine stops within the required time. Test the reset mechanism. Repeat monthly per EN/ISO 13850.

Dimensões

Front 22mm cutout 40mm head Side panel terminals

Diagrama de fiação

L T 21 22 NC (closed) opens on press

Solução de problemas

E-stop won't reset (twist/pull doesn't release)

Check for debris in the mechanism. For twist-release: turn clockwise 45-90 degrees. For push-pull: pull straight out firmly. If the mechanism is stuck, the internal latch may be damaged — replace the entire head assembly.

Machine doesn't stop when e-stop is pressed

Critical safety issue. Immediately lock out the machine. Check wiring — NC contacts must be in series with the safety relay. Verify the safety relay is functioning. A broken wire in an NC circuit should cause a stop, so check for a wiring bypass.

Safety relay faults after e-stop reset

The safety relay detects a cross-fault between the two monitoring channels. Check that both NC contacts on the e-stop are switching simultaneously. One contact may be welded closed — replace the contact block.

Especificações rápidas

Actuator Type
Mushroom Head
Certifications
UL, CSA, CE, IEC 60947-5-5
Color
Red
Contact Configuration
1NC (with ZB4-BZ102)
Cutout Diameter
22mm

O que os usuários dizem

+

“Always use NC contacts, always wire through a safety relay, always test monthly. The Schneider ZB4-BS844 twist-release is my go-to — the trigger guard prevents accidental activation. Never wire an e-stop directly to a contactor.”

Reddit r/PLC by safety_plc_guy 45 votos positivos Ver tópico →

Fontes de dados

Especificações e dados de produto obtidos das seguintes referências.

ZB4BS844 Schneider Product Page

https://www.se.com/us/en/product/ZB4BS844/

Acessado em March 30, 2026

Fonte