Microelectric Actuators for Selectors (Multiposition Valves)

May 2022 - For the foreseeable future, this product is not currently available to purchase due to the worldwide chip shortage. Please contact us to talk about other possible options to serve your needs.

microelectic valve actuator
Multiposition microelectric valve actuator with Valco selector
close move
  • CE-certified
  • Direction reversal
  • Position indication
    • LED display
    • RS-232 output
    • BCD 5V negative true output
  • Manual control
    • Step and home functions
    • Clockwise and counterclockwise functions
  • Remote control
    • Step and home functions with contact closure
    • Direct position access with BCD 5V negative true output
    • Direct position access with RS-232 input (RS-485 optional)
  • Automatic self-alignment with keyed valves and standoffs

One actuator can be used on any selector, from 2 to 96 positions, so you can stock only one type of actuator even if you have a variety of multiposition valves. Valve position memory is maintained even in the event of a power failure.

The direction reversal feature means that if a 6 position stream selection valve is on stream 1 and you select stream 6, you have the option of stepping "backwards" to stream 6 instead of passing through 2, 3, 4, and 5.

RS-232 control offers various commands like position access, direction control, shortest route, etc. (The RS-232 cable must be ordered separately.)

Some valves are harder or easier than others to rotate, so we offer two microelectric models - high speed and high torque. WHICH MODEL DO I NEED? link

Select an item below to view product numbers:

Actuator models

EMH - high speed
EMT - high torque


RS-232 interface
Multidrop (control multiple actuators)
Plug and play

High speed multiposition microelectric actuators - Model EMH

Standard voltage 24 VDC. Autosensing 24 VDC power supply is included.

Hardware Product No.
closemount EMH
2" keyed standoff EMH2
3" keyed standoff EMH3
4" keyed standoff EMH4
6" keyed standoff EMH6
for use w/existing standoff EMHS

High torque multiposition microelectric actuators - Model EMT

Standard voltage 24 VDC. Autosensing 24 VDC power supply is included.

Hardware Product No.
closemount EMT
2" keyed standoff EMT2
3" keyed standoff EMT3
4" keyed standoff EMT4
6" keyed standoff EMT6
for use w/existing standoff EMTS

RS-232 interface cable

An RS-232 cable is required for controlling an actuator from a computer serial port.

Description Product No.
RS-232 interface cable I-22697

Multi-drop cables

Multi-drop cables permit a single serial port to control multiple microelectric two position and multiposition actuators. Multi-drop cables have one female DB9 connector and 2 to 8 male DB9 connectors and are approximately 6" long.

Note: An RS-232 interface cable (I-22697) is required for each actuator controlled serially.

No. of actuators
to be controlled
Product No.
2 I-22897-02
3 I-22897-03
4 I-22897-04
5 I-22897-05
6 I-22897-06
8 I-22897-08

Plug-and-play cables

Plug-and-play cables will allow a direct connection and control between a specific instrument and a multiposition microelectric actuator. Contact technical support for cables for other instruments.

Description Product No.
BCD cable, multiposition microelectric actuator to: Agilent 6890 GC V-EMPMCR-HP6890
Agilent Network 6890 GC V-EMPMCR-HP6890N
Agilent 7890 GC V-EMPMCR-HP6890N
For 4 and 6 column selector* to: Agilent 1100 LC V-EMPMCR-HP1100
Waters Alliance LC V-EMPMCR-WA2690
For 8 and 10 column selector* to: Agilent 1100 LC V-EMPMCR-HP1100-10
Waters Alliance LC V-EMPMCR-WA269010

* Requires a specific software setting in the actuator control module




  • Keyed standoffs are required for the self-alignment feature.
    More link
  • Multi-drop cables permit a single serial port (RS-232) to control multiple actuators. Drawing link
    Serial control of multiple actuators with a multi-drop cable


In the product number tables on this page, an actuator can be specified with closemount hardware, with a standoff (2", 3", 4", or 6"), or with just the standoff mounting hardware, if your valve already has a standoff.

Valves which will be mounted in ovens require a standoff assembly, which locates the actuator out of the heated zone.