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Limit Switches on Velmex Motorized Linear Stages

Limit Switches are electro-mechanical devices that regulate the motion on positioning devices. On Velmex products they are primarily used to stop/turn off the motor when activated preventing over-travel of the carriage/slider. They also can be used to send an event signal. Velmex uses several different types.

• Adjustable (moveable) limits, which are standard on BiSlide Assemblies and optional on XSlide and UniSlide Assemblies.

• Fixed end of travel limits, which are standard on XSlide Assemblies and optional on UniSlide Assemblies. These are not adjustable.

• Internal limits which are only available on the UniSlide MB90 Series.

• Home switches, which actually reference a point rather than limit travel, are used on Rotary Tables and can be used on XSlide Assemblies.

It is possible to purchase motor-driven Velmex stages without limits, however, it is not recommended and it may effect the warranty should you incur any damage.  

The following at-a-glance chart outlines the Velmex Stage and what limits can be used.

  Available Limit Switches  
Velmex Product Adjustable Fixed, End-of-Travel Internal Home Switch
BiSlide® Assemblies Standard N/A N/A Optional* (Mechanical)
UniSlide® MA15 Series Optional Optional (Outboard) N/A Optional* (Mechanical)
UniSlide® MA25 Series Optional Optional (Outboard) N/A Optional* (Mechanical)
UniSlide® MA40 Series Optional Optional N/A Optional* (Mechanical)
UniSlide® MA60 Series Optional Optional N/A Optional* (Mechanical)
UniSlide® MB90 Series Optional Optional Standard Optional* (Mechanical)
UniSlide® XY Tables Optional Optional N/A N/A
XSlide™ Assemblies Optional Standard N/A Optional* (Magnetic)
Rotary Tables N/A N/A (Can be produced with 2 zero reference home switches) N/A Optional (Magnetic)

*Requires an additional control other than VXM™ Controller


BiSlide® Limits
BiSlide Limits

Adjustable limits (standard) - Velmex BiSlide Assemblies have two adjustable limit switches mounted in a track on the side rib of the assembly to prevent over-travel. An optional third limit switch can be added between the two standard limits and used as an adjustable home switch. (This would require a different controller.)

BiSlide limit switches are referenced by either a "-21" or "-31" at the end of the model number. On Parallel-Coupled BiSlide Assemblies, the limits would be eliminated from one of the two linear stages that comprise the assembly.


UniSlide® Limits
UniSlide Adjustable Limits

Adjustable Limits (Optional) - Mounted on the side rib of Velmex UniSlide Assemblies, these two switches can be used to stop travel. These are ordered as a separate part number (OBLS).

Available on all UniSlide Series and UniSlide XY tables

UniSlide Adjustable Limits on MA15 Series

The adjustable limits are located inside a rail that runs the length of the UniSlide® base. A 1/4" cam plate is added to the carriage/slide that depresses the cam when the carriage encounteres it and activates the switch. Thumb locks affix the limit in the proper position. (Pictured: 2 Limits on MA15 Series)

UniSlide Fixed, End-of-travel Limits

Fixed, End-of-travel Limits (Optional) (MA40, MA60, MB90)- These push button switches are fixed on the side rib of Velmex Unislide Assemblies. They are not adjustable. On all UniSlide Series except the MA15 and MA25 the limits are built into the end plate of the slide. On the MA15 and MA25 Series they are outboard switches affixed to the side rib. These are ordered as a separate part number which begins 3-934.

Also availabe on UniSlide XY Tables.

UniSlide Fixed Limits on MA15 and MA25 Series

Fixed, End-of-travel Limits (Optional) (MA15, MA40) - Outboard fixed, end-of-travel limits available on the MA15 and MA25 UniSlide Assemblies.

Internall Limits on MB90 UniSlide

Internal Limits (MB90 "J" Only - Standard) - The internal limits on the MB90 Series consist of two switches, a control rod mounted along side the lead screw with two moveable brass collars and cover atop an additional 3" of dovetail base as shown. The collars are positioned on the control rod to activate the limits. The internal limits on the MA90 Series UniSlide Assembly are referenced by the letter "J" at the end.


XSlide™ Limits
XSlide Fixed Limits

Fixed, End-of-travel Limits (Standard) - XSlide Assemblies have two fixed, end-of-travel limit switches built into the end plates. XSlide fixed limit switches are referenced by either a "-21" or "-71" at the end of the model number.

XSlide Adjustable Limits

Adjustable Limits (Optional) - Moveable limit switches can be added as an option to motorized XSlide Assemblies. These switches can be used to stop travel within the overall travel distance of the XSlide. When installed the adjustable limits reduce travel distance by 1.2" (3.05 cm). These are ordered as a separate part number (XSW-X-PR).

XSlide Homne Switch

Magnetic Reed Home Switch (Optional) - A magnetic reed home switch sets a reference point to return the carriage to home (starting) position. This is moveable. Ordered as a separate part number (XSW-M).

Mechanical home switches can be added to UniSlide and BiSlide linear stages. Switches used in this manner require an additional controller.


Rotary Table Limits
XSlide Adjustable Limits

Magnetic Home Switch (Optional) - A magnetic reed home switch sets a reference point to return the carriage to home (starting) position. This is moveable. Ordered as a separate part number (XSW-M).

XSlide Adjustable Limits

Limit Switches (Optional) - Using two zero-reference (home) switches on a Rotary Table creates limits that restrict travel to a specific degree arc.


Limit Switch Wiring for VXM™ Controller

Limit Switch Wiring

Amp1-480703-0 (mates with:1-480702-0)
*Negative direction on VXM controllers
Connector on Switch Harness are wired on the normally closed (NC) terminals.

CAUTION: The VXM puts 24VDC on the limit switches. Do not connect limit inputs to any +5V logic devices.

Additional information can be found in the VXM™ Users Manual and in the documentation on Limit Switches.


Cable Adapters

Current stages, when ordered with limits, include the appropriate cables to connect to a Velmex controller or flying leads for other devices. We also offer cable adapters to connect older Velmex products.

Rack mount

Cable Adapters – Obsolete motor and limit cables and various adapters are available to connect older Velmex products to current Velmex products.