[How-To] How (can?) a pilot light be added to a 3 phase drum switch?

[Ulma Doctor]

put the indicator 240v light between 2 motor phases.
if the motor turns, the indicator will light up regardless what is up stream

 

[markba633csi]

The problem Mike is that he wants an indicator to light before the motor is started- If I understand correctly
No easy way to do it since the pole-changing switch is cold before the start button is pressed- If I understand the schematic
As he was saying probably putting a cam disc on the switch shaft and a couple microswitches would be the best approach
-Mark
ps I was trying to figure a way to do it with diodes but I'm having some beer and not at my sharpest at the moment

 

[keeena]

@Ulma Doctor - the motor doesn't turn just because the drum switch is on. The logical order of using the lathe: turn the main isolator switch on. Then use the drum switch as the "safety" (off) as well as Speed 1 or 2 selector. Nothing is moving at this point, but locked and loaded. Lastly: the spindle ref/off/fwd lever is used to actually start/stop the spindle.

@Bi11Hudson - yeah, i'm thinking a microswitch could be used on a shaped wheel pressed onto the backside of the drum switch rotor. The wheel would have a flat in the off position, all other orientations will close the switch. If the switch can directly pass 24v AC then I won't need anything else. Seems like the best bet.

@markba633csi - yep, you got it exactly

EDIT - thanks all for the group noodling. I'll follow-up when I cobble something together.

 

[Flyinfool]

It looks like you will have to do something like @Bi11Hudson and @markba633csi suggested with a separate switch on the handle or shaft of the drum switch. There already is 24VAC power available to work with.

 

[tq60]

Thought we had photo of the drum switch, can get one if needed...

Photo is of the main switch, speed adjust control and a meter connected to a control line from VFD that indicates relative speed, can be set to load too.

Ours is VFD and drum switch is logic into the VFD.

A 2P1P 20 amp rated light switch is main power into VFD.

We reconfigured our drum switch as 3 separate circuits by removing The cross jumpers.

Next we bent the contacts so one would always "make" first.

This is the "stop on open" function.

Another closes either position as "run" and the last only one side as "reverse"

For a pilot light we went low tech!

Found a 240 VAC NEON panel mount pilot light and mounted it in the drum switch, it is only 3/8 or so diameter so near the bottom where the power wires would normal be secured.

It is connected to the input to the VFD via fuses.

If main is on and plugged in the pilot glows.

Sent from my SAMSUNG-SM-G930A using Tapatalk

 

[slodat]

Power a pilot light from the 24v transformer secondary. Any time the main disconnect is closed the control power transformer is energized.

 

[keeena]

I cobbled a solution together which works great. The bracket/adapter is 3D printed and designed so it can slide in with the cam wheel installed. The cam wheel was hacked out of scrap just to test; works fine but want to make one a bit more tidy.

3 phase 2 speed drum switch; the axle is pretty short but a press fit wheel w/ set screw got the job done


Bracket