Keystone 051 modulating Valve

[Ones_Zeros]

Hey Guys,
I have an Keystone 051 modulating actuator that I control through Allen Bradley Compact Logic PLC, this actuator is connected to a butterfly valve

I need to make this actuator open slowly, I have contacted the manufactor and looks like I can change this to 38 secs/90°

Is there a better way I can control the speed of how fast this actuator opens this valve in the PLC? I dont want someone to slam this valve open because this is whats currently happening.

Thanks alot

 

[nonuke]

If the voltage to power the actuator is 100 to 240 VAC, you can use a soft-starter to control the ramp time.

 

[Tom Jenkins]

Valve operators often move too fast for my applications as well. I used to order 60 seconds per 90 degree travel, which was usually fine. I used Auma and RCS operators, which could be ordered that way.

You already have the operator, so you are stuck. The best approach is to use a ramp function for the analog signal to the valve. One way, not the most elegant, is to use a resetting timer, say 1 second, and increment or decrement the signal by 0.25 mA (16/60 = 0.27). Keep doing that until the feedback signal or the output signal reach your desired position.

One caution - the Keystone actuators I've used don't have a brake. The motor tends to "flywheel" after the contactor opens, causing some overshoot. This can interfere with accuracy.