Linear Actuator -- Why is this not working?

[trickyrick0465]

I'm using the actuator that says its good for 270lb
https://www.princessauto.com/en/detail/12v-dc-12-in-stroke-270-lb-linear-actuator/A-p8507840e
I'm using the 4rth pully system from here
Pulley diagram
I'm using it to lift 40 lbs
So from the diagram I figured that to lift 40 lbs I need an actuator to handle 160 lbs 4 times what I want to really lift
I'm finding that it struggles to even lift 40 lbs
What am I missing

 

[berkeman]

I'm using the actuator that says its good for 270lb
https://www.princessauto.com/en/detail/12v-dc-12-in-stroke-270-lb-linear-actuator/A-p8507840e
I'm using the 4rth pully system from here
Pulley diagram
I'm using it to lift 40 lbs
So from the diagram I figured that to lift 40 lbs I need an actuator to handle 160 lbs 4 times what I want to really lift
I'm finding that it struggles to even lift 40 lbs
What am I missing

Welcome to PhysicsForums.

What are you using for the 12Vdc 5Amp power source? Could it be drooping?

 

[Lnewqban]

Welcome!
Can you post a picture of the mechanism?

 

[trickyrick0465]

berkeman
Thanks for pointing me in the right direction. The actuator couldn't draw enough current. Switched to a 12V deep cycle battery and works now. I've never used an Actuator when it lifts the weight it sounds like its under a lot of stress.
Thanks guys

 

[Dr.D]

Depending on your system, there can be a lot of friction in that pulley system. This does not seem to be taken into account in your work.