Automated start stop of router

in an effort to automate my single speed router I have bought some of these

http://www.banggood.com/5Pcs-1-Channel-5V-Relay-Module-Shield-Board-For-Arduino-p-952382.html

I have connected the relay thus:

  1. VCC to +5v
  2. IN to A3 (start cooling I dont want spindle speed control)
  3. GND to GND

I have connected 2 of these relays in parallel so as to get 2 pole operation, the output is connected to a socket outlet (receptical if your in the new world) on the NO connections on the relay.

My problem is this, assume I have left the switch on the router on, when I finished off yesterday. I now startup the 24volts transformer to the GRBL etc. and startup the PC and the router starts (potentially a hazard) The router will then stop when press the “open” connection in UCS, I have of course connected to the NO connections as you would expect, connections closing (starting) on command. G0 m8 and stopping G0 m9 so it works OK. BUT I dont like the router starting without sending a command.

I suppose I could use the on off switch but I want this thing automated :slight_smile:

regards Neal

Are you sure that you have the relay hooked to A3. Remember the numbering starts with A0.

On power up/initialization A0 - A2, and A5 are in the high state and A3-A4 are in the low state.

[Edit] PS It’s better to have the USB powered before you turn on the 24 volt power supply. Turn off the 24 volt power supply and then turn off the computer (or unplug the USB cable).

I hooked my relay up to the spindle control.
When using VCarve I make sure to set my RPM to the max so it is effectively on/off.

It has been working well, with the added bonus of being able to use the controller toggle switch to manual turn on the router / shop vac (I have them on the same circuit) if needed.

I suspect there is a way to configure grbl to disable / reconfigure the PWM control into a simple on/off (so I can ignore the RPM settings, Possibly remap the pin?)
But have not had a chance to getting around to it as it has been working well so far.

There is a compile time option to give GRBL that effective disables PWM and makes it revert back to the original model (on/off). However I feel like yourself; Not had a change to change it, and no real need too…

Ok, I was out in the garage to check the connections, I had them connected right!! sort of, I had used A3, but I had connected the output to NO as expected, but NO means normally open without volts, so when I startup the USB because this is on the Arduino, it activates the relay which then changes over and starts up the router, so I need to connect it to NC, its all backwards to me, but seems to work on the m8 and m9 command

So as suggested in your PS @LarryM I have to go through a startup sequence, as I have the 230v on the same contacter as the 24v transformer, if I wait until the USB has got up to speed, and only then start the mains contacter. everything will be good.

thanks for your input @LarryM @AaronMatthews @JeremyJohnstone

regards Neal