How to Manually Drive a Spring Return Actuator
Using a Belimo AFA24-SR I am going to show you how to drive the actuator using a hand crank and also talk about some misconceptions about when does the actuator actually use the spring return.
As I was making this short video at a hospital facility, Mike, one of the facility’s staff was watching just off camera. Once I finished he mentioned to me exactly what I was thinking and hoping for when choosing to create the video. He said,
You know I never actually knew about that manual setting. I just loosen the U bolt and tighten it back down where I need it.
And Mike is not alone. I have come across alot of people, myself included, that in our daily use of various products tend to miss or overlook simple features that could make our lives a little easier.
Manual Adjustment of Actuators
Not all actuators actually have the ability to adjust the action of the actuator without power. Usually, it isn’t all that important to have it after it has been installed and commissioned, but sometimes it really does come in handy for those of us who have to maintain and service the various equipment afterwards.
So, the actuators that can be manipulated manually have some sort of ‘clutch’ or unlocking mechanism that releases it from the motor gearing and allows you to move the action of the actuator freely. Once you release the clutch it then engages the gears and goes back to only moving when given a signal. To keep it where you set it there usually is some sort of switch or clip to hold the clutch in or to tell the actuator to ignore the input signal telling it to drive one way or the other.
Speed of Spring Return Actuators
When specifying or choosing what spring return actuator to use, keep in mind the speed of the run time of the actuators. Almost always the spring return action is a good 5 to 10 Times faster than the speed of the actuator when it is driven using the motor. The AFA24-SR in the video has a run time of 150 seconds using the powered motor and a less than 20 second run time using the spring return.