Konrak Miniature Safety Limit Switch
A miniature safety limit switch with positive-opening (mechanically forced) NC contacts to IEC/EN 60947-5-1. Snap-action or slow-action contact blocks can be combined with a wide range of heads — plungers, roller levers, adjustable arms and whiskers — inside a compact IP66 housing.
One body, many ways to actuate
The T4N is available with a range of heads and actuators so that it can be matched to almost any motion profile.
T4N-□120
Roller lever, resin lever with resin roller
T4N-□122
Roller lever, metal lever with resin roller
T4N-□125
Roller lever, metal lever with metal roller
T4N-□2G / □2H
Adjustable roller lever, metal lever (resin or rubber roller)
T4N-□131 / □132
Top plunger — plain (131) or with ball (132)
T4N-□162 / □172
Unilateral cantilever lever (162) / vertical lever (172)
T4N-□180 / □187
Whisker (180) / plastic stick (187)
Item code — T4N-[conduit][head][contact]. Conduit: 1 = PG13.5 (1 entry), 2 = P1/2 (1), 4 = M20 (1), 5 = PG13.5 (2), 6 = P1/2 (2), 8 = M20 (2). Contact: 1 = 1NC/1NO snap, 2 = 2NC snap, A = 1NC/1NO slow, B = 2NC slow.
Switching capacity
Rated values to IEC/EN 60947-5-1. Continuous thermal current and utilisation categories for the T4N.
| Utilisation category | Rated operational voltage | Rated operational current |
|---|---|---|
| AC-15 | 240 V AC | 3 A |
| DC-13 | 250 V DC | 0.27 A |
Actuation data
Operating forces and travels — matching the switch to your mechanism ensures a reliable, repeatable trip point.
| Actuator / head | OF max | PT max | OT min | TT min |
|---|---|---|---|---|
| Roller lever (snap) | 5.0 N | 18–27° | 40° | 80° |
| Top plunger (snap) | 6.5 N | 2 mm | 4 mm | 6 mm |
| Adjustable lever (snap) | 4.5 N | 18–27° | 40° | 80° |
| Slow-action head | 5.0–6.5 N | 18–27° | 40° | 80° |
Positive opening: POF ≥ 20 N · POT ≥ 50° / 3.2 mm. Values are typical and depend on the head fitted.
T4N technical data
| Housing | Compact reinforced-resin body with a strengthened top seal |
| Contact blocks | 1NC/1NO or 2NC — snap-action or slow-action |
| Positive opening | Yes (NC contacts), symbol per IEC/EN 60947-5-1 |
| Rated insulation voltage (Ui) | 380 V |
| Rated operational voltage (Ue) | 240 V AC · 250 V DC |
| Rated operational current | AC-15 3 A · DC-13 0.27 A |
| Minimum working load | 1 mA / 5 V DC |
| Contact gap | min. 2 × 0.5 mm (snap) · min. 2 × 2 mm (slow action) |
| Electrical life | > 500,000 operations (3 A, AC-250 V resistive), > 300,000 operations (10 A) |
| Mechanical life | > 10,000,000 operations |
| Operating speed | 1 mm/s – 500 mm/s |
| Operating frequency | max. 30 operations / min |
| Contact resistance | ≤ 25 mΩ (initial) |
| Insulation resistance | > 100 MΩ (500 V DC) |
| Dielectric strength | 2.5 kV same polarity · 4 kV other polarity · 6 kV terminal-to-metal |
| Ambient temperature | −20 … +70 °C (no icing or condensation) |
| Humidity | < 95% RH |
| Construction | Class II double insulation · pollution degree 3 |
| Standards | IEC/EN 60947-5-1 (positive opening) |
| Marking | CE · CCC |
Values shown are typical for this series — please confirm against the current datasheet and drawing for the exact variant required.
Why choose the T4N
Positive opening
The NC contacts open mechanically under a forced action, giving a reliable safety function to IEC/EN 60947-5-1.
IP66 sealed
A strengthened top-seal structure protects the mechanism against dust and powerful water jets.
Snap or slow action
Snap-action and slow-action contact blocks are available with 1NC/1NO or 2NC contact arrangements.
Wide actuator range
Plungers, roller levers, adjustable arms, whiskers and plastic sticks — a head for almost any motion profile.
Long life
> 10 million mechanical operations and > 500,000 electrical operations at rated load.
Double insulation
Class II construction for extra safety — no protective earth connection to the enclosure is required.
Compact size
A small footprint makes the T4N easy to integrate where space is limited.
Adjustable heads
Lever length and angle can be adjusted to fine-tune the operating point.
Where the T4N is used
Machine tools and CNC
Position and end-of-travel detection on slides, spindles and tool changers.
Guards and safety doors
Positive-opening interlocks monitor protective guards and access doors.
Conveyors and packaging
Detection of product position, accumulation and end stops.
Lifts and elevators
Levelling, door position and limit (terminal) stopping.
Valves and dampers
End-position feedback on actuated valves and dampers.
Automation and robotics
Precise position sensing on linear and rotary axes.
Frequently asked questions
What does 'positive opening' mean?
The NC contacts are opened mechanically by a rigid link rather than by spring force, so they open even if a contact sticks — required for machine-safety circuits.
Which contact blocks are available?
1NC/1NO or 2NC contacts, in snap-action or slow-action versions.
What is the degree of protection?
IP66 — dust-tight and protected against powerful water jets.
What actuators can be fitted?
Top plungers, roller levers, adjustable levers, cantilever and vertical levers, whiskers and plastic sticks.
How long does it last?
> 10,000,000 mechanical operations; electrical life is > 500,000 operations at 3 A / AC-250 V.
How is it mounted and wired?
Standard mounting holes suit direct fixing, and the conduit entry can be PG13.5, P1/2 or M20 in single- or double-entry versions.
Need the right T4N limit switch?
Tell us the actuator, the contact arrangement and the mounting you need — our team will confirm the exact model and can supply samples or OEM versions.
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