The Moujen MN-5121 is a roller lever mini limit switch from the MN side mount series, rated 10A at 250V AC. It detects when a moving part reaches a set position and switches the control circuit, with the roller riding against the cam or dog rather than scraping across it.

That roller is what keeps the switch accurate over long service. A sliding cam wears down a plain lever tip, which shifts the trip point a little further each month until the machine stops stopping where it should. With a roller, friction stays low and the switch trips at the same place after thousands of cycles.

The side mount body fixes flat along a machine frame or guide rail, so the switch sits out of the way of the moving part instead of in front of it. Oil tight and waterproof construction with IP65 sealing keeps coolant, dust and washdown water out of the contacts, which is what matters in a machine shop. At 10A 250V AC it switches AC control circuits directly, and the 0.5A 125V DC rating covers PLC input duty.

Key Features

Roller lever actuator reduces wear from sliding cams
Side mount body fits flat against frames and rails
10A at 250V AC for direct control circuit switching
0.5A at 125V DC for PLC and low current DC signals
Fine operating speed range from 0.01mm to 50cm per second
IP65 sealing with oil tight and waterproof construction
UL Listed and CE Mark certified
Compact 0.1kg body for tight installations

Technical Specifications

Specification	Detail
Product Type	Side Mount Mini Limit Switch
Range of Product	MN Series
Model	MN-5121
Actuator	Roller Lever
Mounting	Side Mount
AC Rating	10A 250V AC
DC Rating	0.5A 125V DC
Operating Speed	0.01mm to 50cm per second
Degree of Protection	IP65
Construction	Oil Tight and Waterproof
Certification	UL Listed, CE Mark
Brand	Moujen
Country of Origin	Taiwan
Weight	0.1kg
SKU	MN5121

Common Applications

End of travel detection on conveyors and slides, carriage position sensing on machine tools, cam operated sequencing, guard and cover interlocks, packaging and assembly line stop positions, sliding door and gate detection, and repeat cycle duty where a plain lever would wear out.

Related Limit Switches

Actuator type decides the model, so pick by how the moving part reaches the switch. For a fixed lever without a roller, the lever limit switch AZ-7120 is a lower cost side mount option. Where the contact point varies, the adjustable roller lever limit switch AZ-8108 lets you set the lever length, and the adjustable rod limit switch AZ-8107 reaches targets a lever cannot.

For a push straight onto the switch, see the cross roller plunger limit switch ME-8122 or the roller plunger limit switch AM-1308 at 15A. Where an overrun could snap a rigid actuator, the spring limit switch AZ-8166 flexes and returns. For heavy equipment, the big wheel limit switch AZ-5108L and the 10A adjustable roller lever limit switch AZ-5108 have larger, tougher bodies.

Browse the full side mount limit switch range, or see every actuator type and rating in the limit and micro switches category.

Why Buy From Qahraba

Qahraba supplies electrical contractors, panel builders and machine builders across the UAE and worldwide. Every limit switch we stock is genuine Moujen product with full certification. Local UAE orders ship within 1 to 2 working days, free above AED 250, or collect free from our Dubai store. Call or WhatsApp +971 52 913 9543 for bulk pricing.

FAQ,s

What is a mini limit switch?

It is a compact position detection switch. When a moving part presses the actuator, the internal contacts change state and signal the controller to stop, reverse or move to the next step. The mini body fits where a full size switch will not.

Why choose a roller lever over a plain lever?

A roller turns as the cam passes, so it wears far less than a lever tip scraping across the same surface. On repeat cycle machines this keeps the trip point consistent for much longer.

What does side mount mean?

The switch fixes flat against a surface on its side, so it can sit along a machine frame or guide rail and meet the moving part from the side rather than head on.

Can the MN-5121 connect to a PLC?

Yes. The 0.5A 125V DC rating covers standard 24V DC PLC inputs, and the 10A 250V AC rating allows direct switching of AC control circuits.

Is it suitable for oily or wet areas?

Yes. The body is oil tight and waterproof with IP65 sealing, which suits machine tools using coolant and areas exposed to splashing.

What contact arrangement does it have?

Contact configuration depends on the variant. Call or WhatsApp +971 52 913 9543 and we will confirm the exact arrangement before you order.

Roller Lever Mini Limit Switch 10A IP65 MN-5121 Moujen