STI-6517

Active
UL CE

Stopper II Push Button Cover No Horn

STI (Safety Technology International) Stopper II Series Introduced circa 1990

STI Stopper II without horn — silent protective cover.

Common Applications

Same polycarbonate protection without the alarm horn. Used over e-stops and critical buttons where the visual deterrent is enough. Also used over buttons that are accessed frequently but need protection from accidental bumps.

Specifications

Certifications
UL, CE
Color
Red/Green/Yellow/Clear
Material
Polycarbonate
Mounting Type
Surface mount over existing button

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

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

$53.94 — $142.78

across 2 distributors

Quick Specs

Certifications
UL, CE
Color
Red/Green/Yellow/Clear
Material
Polycarbonate
Mounting Type
Surface mount over existing button

What People Are Saying

“Same polycarbonate protection without the alarm horn. Used over e-stops and critical buttons where the visual deterrent is enough. Also used over buttons that are accessed frequently but need protecti”

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