IMER Mortarman 120 Plus Mixer Emergency Stop Button

Features

• Replacement stop for Mortarman 120, and step up 120 pump
• Large red emergency stop push button, part of the Mortarman 120 Plus switch box

The Imer Mortarman 120 Plus Mixer Emergency Stop Button is a large red safety push‑button mounted on the Mortarman MIX 120 Plus control box that lets the operator instantly shut down the mixer in any emergency, protecting both the user and the machine. Sold as OEM part number 3225237 (superseded in some catalogs by 3225440), this replacement stop button is specifically designed for the Mortarman 120 / MIX 120 Plus vertical shaft mixer and is also used on compatible IMER Step‑Up 120 pumps.

What is the Imer Mortarman 120 Plus Mixer Emergency Stop Button?

Distributors list this part as “IMER Mortarman 120 Plus Mixer Emergency Stop Button” or “PN 3225237 IMER Mortarman MIX 120 Plus Mixer Emergency Stop Button.” It is a:

• Large red emergency stop push button, installed as part of the Mortarman 120 Plus switch box / control panel.

• Replacement stop for Mortarman 120 mixer and Step‑Up 120 pump control panels.

The MIX 120 Plus manual calls this device the “emergency button / safety catch button” and shows it in the electrical schematic as P1 – SAFETY CATCH BUTTON. It is the primary emergency‑stop control described in the operator’s safety instructions.

OEM Part Numbers and Supersession

The main OEM part number associated with the Mortarman 120 Plus emergency stop button is:

• 3225237 – Imer Emergency Push Button / Safety Catch Button.

Some parts distributors note that:

• 3225440 IMER emergency button replaced 3225237 in later screw‑pump/control panel configurations.

For most Mortarman MIX 120 Plus mixer applications, retailers and IMER USA Direct still reference PN 3225237 as the correct emergency stop button.

When ordering, you should confirm whether your control panel calls for 3225237 or the updated 3225440 part, especially if you are working on newer Step‑Up 120 screw pumps that share similar control boxes.

Location and Function on the Mortarman 120 Plus Mixer

The Mortarman 120 Plus is a vertical‑shaft mortar mixer with an integrated control cabinet on the frame. The manual describes the mixer layout as:

• Ref. 5 – Motor.

• Ref. 6 – Reduction gear.

• Ref. 8 – Start and stop switch on the electrical cabinet.

• Emergency stop button on the control panel.

In the user instructions, IMER explains:

• “In case of emergency, stop the machine by pressing the emergency button. Then pull out its power plug. To start again, reconnect the power plug and turn the power switch to ‘1’.”

The emergency stop button:

• Immediately cuts power to the mixer motor when pressed.

• Works in conjunction with other electrical safety devices such as the main switch, contactor, overload thermal cutout, and tank guard interlock.

• Must be reset according to the control panel design before the mixer can be restarted (typically by releasing or twisting the E‑stop, then switching the main power back to “1”).

In the wiring diagram, the emergency button is labeled P1 – SAFETY CATCH BUTTON, wired in series with the contactor (KM1), inverter (IM1), limit switch (FCS), and thermal protection (TM1). If P1 is activated, the control circuit opens and the mixer stops.

Safety Role and Manual Instructions

The Mortarman 120 Plus is built to EN 60204‑1 electrical safety standards and includes multiple protective systems:

• IP55‑rated electrical cabinet with protections against water jets and automatic restart after power failure.

• Mechanical guards on hazardous areas such as the drive belt.

• A tank guard with an interlock that prevents operation when open.

Within this safety system, the emergency stop button is the operator’s primary quick‑action control. The manual emphasizes:

• “12. EMERGENCY ‑ STOP – In case of emergency, stop the machine by pressing the emergency button. Then pull out its power plug.”

• The mixer should be stopped with the main switch for normal operations and never by improvised methods.

This makes the emergency button a critical safety component: it must be present, functional, and easily accessible whenever the mixer is in use.

When to Replace the Imer Mortarman 120 Plus Emergency Stop Button

You should replace the Imer Mortarman 120 Plus Mixer Emergency Stop Button whenever:

• The button does not latch or release correctly, or feels loose or inconsistent.

• It shows visible damage, cracks, or burnt contacts.

• The mixer does not stop when the emergency button is pressed (after ruling out wiring issues or contactor faults).

• The button has been damaged by impact, water ingress, or corrosion.

Because the emergency stop is that last line of defense, IMER and dealers treat it as a safety‑critical part; if there is any doubt about its condition, replacing it with OEM PN 3225237 (or the superseding 3225440 if specified) is recommended.

Compatibility: Mortarman 120 Plus and Step-Up 120

Contractors Direct and Blades Direct both highlight that this emergency stop button is:

• A “Replacement stop for Mortarman 120, and Step‑Up 120 pump.”

That means:

• It fits the Mortarman MIX 120 Plus vertical shaft mixer control panel.

• It also fits certain Step‑Up 120 pump control boxes, which share similar electrical enclosures and emergency stop layouts.

If you service both mixers and pumps from IMER, keeping a spare 3225237 emergency stop button on hand can cover multiple machines.

How the E‑Stop Interacts with Other Electrical Components

The Mortarman 120 Plus wiring diagram shows the emergency stop button as part of a broader control circuit:

• P1 – Safety catch button (emergency stop).

• IM1 – Inverter controlling the mixer motor speed/drive.

• KM1 – Contactor that energizes the motor circuit.

• FCS – Limit switch (e.g., tank guard interlock).

• TM1 – Thermal protection (overload safety).

• F1 – Fuse carrier, C1 – Capacitor, and R1 – Resistor as additional circuit elements.

Pressing the E‑stop opens the circuit at P1, de‑energizing KM1 and IM1 so the motor stops. Any fault or replacement that bypasses or incorrectly wires this button can:

• Compromise safety by preventing reliable emergency stopping.

• Conflict with other protections like the thermal overload or limit switch.

Using the correct OEM emergency button and following IMER’s wiring diagram ensures the control panel maintains its original safety functions.