Contactor not engaging without help

[drodda]

I have a prt alpha and tonight the router would not turn on when you hit the green start button. So I open the box and tried it a few times. I have traced the problem to the contactor above the one the router is hooked to. The router contactor snaps in when started but the top one does not. With a little help from a screwdriver it does engage. Does anyone have a part number or replacement cross reference for the contactors? Are all 110 volt contactors alike? I would like to replace this but really don't want to wait for delivery from shopbot sometime next week.

[GlenP]

Dave. Sounds to me like the coil is getting weak on the the contactor. You can replace with a different brand as long as the coil rating is for the same voltage and the contacts are rated for the same load. If you want to keep operating could you not disconnect the wires on the contactor contacts and connect them together bypassing the router contactor to turn it on and off. You would them have to use the on/ off switch on the router until new part arrived.

[3imoh]

I am not near my control box, so someone please correct me if I am wrong, but I thought there were two identical contractors wired in series as a redundant safety feature. Couldn't you just bypass the bad one until you get a replacement? You would still have the SB controlling the power.

-Howie

[drodda]

There are two wired in series. What supplys the control voltage to each? Or are the just totally redundant? My thought would be that they are ran from two different control voltage sources? Just making sure that it is not another issue such as with the board or something else that sends the control voltage to the top contactor. When I check the bottom one I get 55 volts for control voltage. but I don't seem to get anything fro the top one?

After pushing in the front of the contactor many times it seems to work again. However I am still wanting to replace this so I don't have issues in the future.

It seems my bot only has trouble on Saturday nights after 10pm? This is always very frustrating as I usually work saturday and sundays these days trying to keep up with things.


Thanks for the help.

[ted]

Hi Dave,

If you check in with us on Monday, we'll send you one. We've had a few sticky contactors.

They are installed in pairs for redundancy (an industrial controller practice).

[Slightly loosening the screws that hold the feet of the contactor in place may free it up.]

Ted Hall, ShopBot Tools

[drodda]

Another fine example of why I selected Shopbot when I was researching what CNC to buy. Today I received two emails from Shopbot support on this issue and also had the last post by the "Big Guy" himself. Could you ask for any better support for a product?