Emergency Push Button with NC
Emergency Push Button with NC
Blog Article
An Emergency Push Button (NC - Normally Closed) is a critical safety device used to immediately cut power to machinery or equipment in emergencies. Below are the key details:
???? Key Features of Emergency Stop (E-Stop) Button (NC):
Contact Type: Normally Closed (NC) – Circuit is broken when pressed (failsafe design).
Function: Instantly cuts power to hazardous machinery (meets ISO 13850, IEC 60947-5-1).
Actuation: Mushroom-head button (large, red, and easy to press).
Reset Mechanism: Manual twist-release or key-release (prevents accidental restart).
IP Rating: Typically IP65 (dustproof and water-resistant for industrial use).
Terminals: Screw or spring-clamp connections.
???? Wiring (NC Emergency Stop):
NC contacts are wired in series with the control circuit (breaking the circuit when pressed).
Example:
Connect the E-stop NC contact to de-energize the contactor coil (e.g., Telemecanique LC1D or ABB AF series).
Requires manual reset to restart the system.
???? Common Models:
Schneider Electric (Telemecanique) XB4BS8445
Red mushroom-head, NC contact, 1NO + 1NC, IP65.
Siemens 3SB3800-1AA21
Plastic head, NC contact, twist-to-reset, IP65.
ABB 1SFA611104R1000 (Emergency Stop Station)
Metal head, NC contacts, key-release reset.
Allen-Bradley 800E-X4A1
30mm diameter, NC contact, rugged metal design.
⚠️ Safety Standards:
ISO 13850 (Emergency stop function principles).
IEC 60947-5-1 (Low-voltage switchgear standards).
EN 60204-1 (Safety of machinery).
???? Installation Tips:
Mount in easily accessible locations.
Use dual-channel wiring (redundant NC contacts) for safety-critical systems (PL e/Cat. 4).
Test regularly to ensure proper function.
???? Alternatives (NC Emergency Buttons):
Omron A165E-M-12 (Small footprint, NC contacts).
Eaton M22-D-X1K (22mm diameter, rugged metal).https://store.unigulfsupply.com/product/emergency-push-button-xb4bs8444/