Scs300 jamming up CB1 control panel

[Steeves]

Hi, after a bit of help. A friend has a set of liftmaster scs300 240v gate arms, controlled by a cb1 panel. A few weeks back one of the arms stopped working on and off etc. It would work for a bit then seamed to jam up on the end of its travel when the gate was closed. The motor would run but would just hum as if it was jammed up. If you released the lock and then engage it again it would continue to open, then close but again it would jam up. There is a physical stop at both closed and open but nothing that would stop the gate from opening etc.

He ended up buying a replacement arm thinking that the original one was broke, but after fitting this for him, we got the same problem.
The gate will close fine but when it starts to open it will just hum until I unlock it manually then egage it again and it runs fine. It’s like as if the bush is getting jammed up on the worm screw or the arm cover but there is nothing physically in the way ?

Could it be that it requires more force and M2 (potentiometer) is broke ?
Any help or advice would be much appreciated
Thanks Steve

[Tim]

Hi Steve,

Thank you for your enquiry, normally if a 230v motor hums then it is the capacitor that has failed. I would advise you to swap the capacitors over from the working motor to the motor that is jamming and see if the fault moves to the other motor. I would also advise you to reprogram the open and close limits on the board to see if that helps with the problem.

If the system was working fine for a long period of time before this motor started to cause problems then i wouldn't of thought it will be a problem with motor force. If you are going to adjust the force to the motors then you will have to pay attention to the safety on that system to make sure it meets up to date legislation to gate safety and machinery directive. Hope this is usefull information for you.

Tim