DC controller for liner actuator

I am working on a project to motorize the chute deflector of a snowblower. I am considering using the LACT4P-12V-05, or if I need more range, the LACT6P-12V-10. I see that the Jrk G2 21v3 is one of the suggested controllers. I have some questions:

  1. The 21V3 is rated at 2.6 amps without heat sink, but the actuator has a max current of 3.2 amps. While the load presented by the deflector will be low, there may be times where it may reach 3.2A. Do you have any idea of the current that could be supported by gluing on a heat sink? (the next Jrk model is too pricey for the project) . I would have to move to other brand and or to a plain driver.

  2. Is there a way to read the current from the Jrk or to get a stall alarm? I am affraid that if the actuactor reaches the ends of the mechanical trip of the deflector, it may cause damage. I know the Glideforce has limit switches, but it is conceivable, specially during tuning, that they may not be adjusted slightly narrower that the physical trip of the deflector. So I would like to detect stall and kill operation.

Any suggestions will be appreciated.


The Jrk G2 21v3 's 2.6A figure is for continuous current with 5A being the peak. I suspect you aren’t really going to be running the actuator continuously at 3.2A, so it will probably be fine. We have not characterized how much improvement the Jrk G2 would be capable of with a heat sink added, but I generally expect forced airflow to be a more effective method of cooling.

The Jrk G2 21v3 has a “soft current limit” setting that will trigger an error flag if exceeded. You can configure the threshold current for this error under the “Motor” tab of the Jrk G2 Configuration Utility software. The Jrk controller’s response to the error can be configured in the “Errors” tab of the same software. You can find more details about these options in the ["Error handling"0 section of the Jrk G2 user’s guide. Additionally, you can read the error flags via TTL serial, I2C, or, USB using the respective “Get variables” command. Information about this command can be found in the “Command reference” section of the same user’s guide.

Since it looks like you are planning on using actuators with feedback, note that you can also specify a maximum allowable position. For example, you can set the Minimum and Maximum settings in the “Feedback” tab of the Jrk G2 Configuration Utility to throw an error if they are outside of the specified range. You can also set a Minimum and Maximum “Target” in the Input tab to prevent the Jrk from trying to send the actuator to a position outside the range of your system.


Brandon, thank you for the detailed answer. It looks like the G2 21V3 is a good fit.

Do you see any problems having the G2 some 3’ to 4’ away from the linear actuator? It will bridge over the motor, so it may be exposed to some spark plug noise. I may have to run separate grounds for motor and feedback. I would cut the actuator cord short and splice it in a small box to switch to silicone wiring for better flexibility under cold temperatures. The cabling has to allow for the chute turning.

If you need to have the system spread over a larger area, it is typically better to keep the controller closer to the input signals and the longer length of wire between the controller and the motor, so it sounds like you are already doing that. It is hard to say if the motor will cause enough electrical noise on the feedback line to disturb the system. The Jrk G2 controllers do some sampling of the feedback to try to filter out some noise, and if you have problems with noise you could try adjusting the “Analog samples” value and PID period to see if that helps. You can find more information about how those settings work when using analog feedback in the “Analog/frequency feedback handling” section of the Jrk G2 user’s guide.