An electrician installed a screw type compressor. 230Volt, 3-phase, 10HP name plate ratings stated 45Amp and 60Amp breaker. #6 wire was pulled from starter (in emt conduit) to disconnect switch. From disconnect switch to motor flexible conduit was used. The wires in the conduit run from the starter to the disconnect are vibrating. Nothing else is vibrating. You can see and feel the vibration at the starter and hear the wires banging in the conduit. This only happens at startup. Electrician checked loads and everything is within tolerances. The entire conduit run is less than 25 feet. Any suggetions on what to check?
Wires Vibrating
- Thread starter KMark5710
- Start date
- Status
- Location
- Massachusetts
Nothing, unless the noise bothers you.
You could pull the wires out and pull them in again which might change how they are lying in the conduit.
You could pull them out and twist them together like a triplex cable and that will stop it.
You could replace the 6 AWG with larger.
About the only down side of this is the noise and it might at some point vibrate enough to wear the insulation off in a spot but I have been in highrises that where 35 years old and every time one of the 8 elevators started its feeder vibrated.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
The high start up current of the motor is causing the conductors to vibrate, (there pushing apart in the conduit) you can pull them back out and tape them together every 12", since its a short run. But as iwire said, its nothing abnormal.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Go back to the fundementals and pay attention to the force created by the Right Hand Rule. Remember to take into account the effect of the back EMF from the induced currents in the ferrous metals present.
- Status