Electrical question - how to indicate something's plugged in?

[Michael Press]

I'm building a router table. I'm going to put an electrical outlet and switch on the table so the router can be turned on using the switch instead of having to reach under the table to find the router switch. I'll unplug the router from the table's outlet to change bits. All this wiring I can handle.

Here's my question - I'd like to have a light that shows whether the router is plugged in - just to make sure that the router can't be powered on (like if the switch is accidently turned on) while I'm changing a bit. The light should be on whether the switch is on or off, but only if the router is plugged in.

Is this possible?

Thanks, Michael

[Speedy Jim]

Instead of a complicated electrical circuit, how about designing some simple mechanical "flag" which would have to be manually raised in order to insert the plug.

Or, attach a magnet to the cord plug and let it actuate a reed switch (burglar alarm contact) and a small lamp.

Jim

[Anthony Diodati]

[Nate B]

"Michael Press"

To show if it's plugged in, you will need to tap into the circuit between the plug and the router motor. Personally, I would consider soldering a couple ~20 gage wires to some terminals inside the router's plastic casing, and let those lead to a 120 V LED of choice, which you can get at Radio Shack. You could even put a another connector somewhere near the outside of the plastic case so the long wire would be removable.

However - I think what you really want is something just showing if the circuit/outlet has power. I think Home Despot or someone else probably sells a lighted, switched outlet. ie, switch, light and outlet in 1 single position box. I certainly know lighted 120 V rocker type panel switches are commonly available from places like radio shack, so at the least, you could put one in before the outlet. Just make sure it can handle the 15-20 amps you'll need.

- Nate

[volts500]

Woods Industries makes a lighted adapter (No. 2525) that will plug into the receptacle, then plug the router into the lighted adapter. Great for making a lighted extension cord out of a regular extension cord too. Check your local hardware store(s).

[SQLit]

This will only tell you that there is power available. Not if the router is plugged in. Good idea though

[Toller]

It is possible, but not easy. You would need double throw switch. One way puts 1.5vdc through the router and a flashlight bulb in series; the other way puts 120vac through the router and a nightlight bulb in parallel.

I am assuming here that 1.5vdc will not hurt your router; I don't actually know that and suggest you confirm it before doing it.

But frankly it seems like way too much trouble. I make it a point to unplug my router before changing bits and have not yet had a problem remember (that I am aware of).

[Toller]

If the switch is off you have no power to the plug and no power to the LED. And when the switch is on, so is the router, so you hardly need the LED unless you are deaf.

[Max]

a simple way to force the issue is to tie the collet wrench to the plug with a shortish string - short enough not to reach the router when plugged in, but long enough not to interfere with wrench usage when unplugged.

Maybe he could put a clip on the back of the table to hold the plug while using the wrench so the plug isn't flapping around in the work area. bad da bing badda boom.

This is also 100000000000000X safer than the light idea.

total time for job: 45 seconds.

.max

[volts500]

The OP stated that the outlet and the switch will be mounted on the table. How hard is it to glance at the lighted adapter before changing a bit, or even a (preferably red) lighted indicator switch? In addition to seeing that power was available or not, would he not also SEE that the router is plugged in? I think what he's really looking for is a quick way to safely change a bit, in which case he may want to consider purchasing more than one router if he wants to be Quicks Draw McGraw.

[John Grabowski]

Off hand the only way I can think of to do this is using a 5 wire plug and receptacle (NEMA L22-20P and L22-20R 20 amp). You didn't mention the amperage and voltage of your machine, but I'm presuming it is 120 volts.

Wire the ground pin like you normally would. Use 2 pins for the feed for the router. Put a jumper in the plug between the 2 unused pins. That jumper will act like a switch whenever the plug is put into the receptacle. Of course this creates a dangerous situation (Dead short) if you were to plug this into a normally wired 5 wire receptacle. If this is a residence it is unlikely that you will have many 5 wire receptacles around.

Inside of the junction box housing the receptacle you will need to wire the corresponding pins for the power feed to the router. The receptacle pins for the indicator light should have the hot leg looped through the plug.

I suggest that you use the same circuit for the light as well as the router.

I strongly advise against doing it this way. I would use a pilot light switch and also a plug with a pilot light in it.

John Grabowski

[John Hines]

A real simple answer, attach the router chuck wrench to the power cable, up near the plug.

This way you can not (unless you go through extremes) change the bit, without unplugging it.

Works real good on drills as well, to keep from loosing the chuck key.

[Michael Press]

I don't think you understand my intent. The lighted outlet only shows whether the switch is on or off. I already have a great way to tell if the switch is on - the router is on.

Here's the scenario I'm trying to avoid - Turn off the switch, start changing a bit without unplugging the router, accidentally hit the switch, router puts nice dado in finger.

The lighted outlet doesn't help - it's off whether the router is plugged in or not. It's on when the switch is on, which doesn't help either.

Michael

[Steve Nekias]

You can purchase single pole electrical switches for household wiring use that illuminates when in the "on" position.

This isn't quite what you wanted, but it might work for you--and it would be cheap.

Steve

[Nehmo Sergheyev]

- Michael Press -

- Nehmo -

If the router has a ground wire. Connect like this:

Ground inside receptacle------LED--Battery----Ground wire inside router

When the router is unplugged the circuit is incomplete and the light is off. When the router is plugged in, the ground wires connect and the light goes on.

A dead battery will also produce a light-off condition. So unplug the router when not in use and use a lithium battery. It will last a long time that way.

[Nate Weber]

I'm assuming the router would be semi-permanently mounted to the table. I would remove the routers original cord completely then make a new cord with a handy box in the middle. Mount a light in the box and wire it between Line and Neutral. I wouldn't want to rely on a light to tell me if the router was unplugged though. Lights can burn out, especially with the routers vibration.

Nate

--

[volts500]

Then you'll want a guarded motor starter switch or possibly a 20 amp Decora Plus (Commercial) rocker switch with a weatherproof GFCI cover that has the spring loaded closure.

[RB]

The smart way to do this is to unplug the tool. Any other way means you don't care if you have ten, or perhaps nine or less fingers. It's your call.

RB

Michael Press wrote:

[Micro*]

Simple, place a neon indicator or 120v rated led in parallel with the switch, with router plugged in circuit is complete to lamp (only small current need to light neon or led) with unplugged no circuit.

-- "Shut up and keep diggen" Jerry

[Toller]

It took a while, but we got some clever solutions. However, it was pointed out that this is subject to false negatives, which are dangerous. How about the opposite; it turns a light out when the router is plugged in. That gives only false positives, which are harmless. You could even use the light to help you change the bit!