[naspc]

Does any one know the limit switch input voltage on a mx3660? I am looking at some limit sensor that are 5volts.

[Little_Chips]

This does not answer your question directly but gives you a couple of methods to get the answer if no one knowing responds.

Much of the time a switches rating is printed on the switch. You may also have a meter to measure if the switch has 115VAC or 5VDC or some other voltage on it. If the switch is stuck open simply measure for presence of voltage across the switch contacts. If the switch is stuck closed (shorted) then one of the wires will have to be disconnected from the switch after removing main power, secure the wire such that it can't short to anything, then reapply power and measure between the two wires that go to the switch for presence of a DC or AC voltage. Sorry I do not know if your system uses AC or DC on the limit switch. Regardless measuring for either AC or DC volts with a multimeter will not harm the meter so long as you start on a high range on the meter working your way down in measurement range till you get a reading on the meter. If you have an auto ranging meter then you don't have to worry about starting at a high range and working your way down the scale.

[CitizenOfDreams]

A sensor with an open collector output will work regardless of the board input voltage (which the MX3660 manual does not seem to list, but my wild guess is that it's somewhere around 12 volts).

[naspc]

Thanks everyone. I finally did confirmation the output is 12V.
The limit sensor is 3.3V sensor made by creltek
https://www.tindie.com/products/kevpatt/creltek-limit-sensor-343rt/.
Looks like they have a regulator to address the voltage difference. Will need to do testing.

[CitizenOfDreams]

https://www.tindie.com/products/kevp...-sensor-343rt/.
Looks like they have a regulator to address the voltage difference. Will need to do testing.

Attachment 323658
Actually, from what I can guess by looking at the circuit board, there is no voltage regulator. Just the all-in-one Hall effect sensor chip (U1). The chip can be powered by either 3V or 5V, and most likely it has an open collector output - which allows it to be used with inputs pulled up to voltages higher than Vcc.
The transistor (Q1) is just the driver for the LED (D1).

[naspc]

Attachment 323658
Actually, from what I can guess by looking at the circuit board, there is no voltage regulator. Just the all-in-one Hall effect sensor chip (U1). The chip can be powered by either 3V or 5V, and most likely it has an open collector output - which allows it to be used with inputs pulled up to voltages higher than Vcc.
The transistor (Q1) is just the driver for the LED (D1).

Will this work with the mx3660 without a regulator?

[CitizenOfDreams]

Will this work with the mx3660 without a regulator?

MX3660 does not have any 5V or 3.3V output (or any other power output), so you have to get it somewhere else. Either with a voltage regulator, or with a separate AC power supply. Do you have a +5V power source anywhere in your machine?

[CitizenOfDreams]

By the way, what made you choose this naked homebrewed circuit board instead of a finished product like this?
Attachment 323666
10pcs New LJ12A3 4 Z BX Inductive Proximity Sensor Switch NPN DC6 36V | eBay

[naspc]

By the way, what made you choose this naked homebrewed circuit board instead of a finished product like this?
Attachment 323666
10pcs New LJ12A3 4 Z BX Inductive Proximity Sensor Switch NPN DC6 36V | eBay

You are right about the 5V. MX3660 does not output 5V, from support they did confirm 12V. Was think about using the following to get the 3.3 or 5 from the MX3660.

https://www.tindie.com/products/kevpatt/creltek-3a-switching-regulator-1s10/

I thought the idea of something different was intriguing, I like the idea of the LED for confirmation.

[CitizenOfDreams]

You are right about the 5V. MX3660 does not output 5V butfrom support they did confirm 12V.

Just to clarify, the 12V we are talking about here is the pull-up voltage for the inputs. There is no 12V power coming out of MX3660, unless you open it up and solder your own wire to its internal 12V regulator.

[naspc]

Just to clarify, the 12V we are talking about here is the pull-up voltage for the inputs. There is no 12V power coming out of MX3660, unless you open it up and solder your own wire to its internal 12V regulator.

Might have confused the support guy. Here's what the sent me.

[CitizenOfDreams]

And yes, trying something different is a perfectly good reason. It's just that building a CNC machine has plenty of other exciting challenges besides reinventing the limit switch.

[CitizenOfDreams]

Might have confused the support guy. Here's what the sent me.

That's strange, I did not see the +12V output in this MX3660 manual: http://www.npoatom.ru/upload/2_MX3660.pdf
Are we possibly talking about two different products by the same name?

[naspc]

That's strange, I did not see the +12V output in this MX3660 manual: http://www.npoatom.ru/upload/2_MX3660.pdf
Are we possibly talking about two different products by the same name?

I think I know what he is talking about. Look at this diagram using a proximity sensor on the left side. This may reinforce your statement about a external power source.

[naspc]

Just email from the guy who makes the sensors:

I did a little research on your MX3660 controller. It does appear that the digital inputs source +12V. My limit sensors are designed to work with input voltages between 3V and 6V. They do not include an on-board regulator as that would add too much cost to each individual board. I did a quick calculation, and with a 12V input the sensor should work fine but the indicator LED will be driven at about 36 mA. The LED is rated for 20 mA. I’m not sure if 36 mA would burn it out but it would certainly be VERY bright.

The RJ-11 Sensor Breakout board does include an on-board 3.3v regulator. However, the outputs from the breakout board back to your controller’s digital inputs would be logic signals that are 3.3V when “open” and 0V when “closed”. Whether it will work with your system in particular depends on how your controller interprets these voltage ranges. The easiest way to find out is simply to try it and see.

I can modify the limit sensors themselves to function directly on 12V, which would be the ideal solution for your system. However, I will have to use a new batch of boards, so I wouldn’t be able to ship your 12V sensors until the week of July 4. I am willing to customize them for you at no additional cost, and if you order 6 or more they will only be $5 each. The modified 12V sensors can still be used with the RJ-11 Sensor Breakout board that you ordered; you’ll just need to remove the solder jumper for the on-board 3.3v regulator (easy). So the only downside for you would be the approx. 3 week delay.

[naspc]

This idea might not pan out. I might be going with the proximity sensors recommend earlier.

Any idea how to wire them up to a mx3660?

There's only 4 inputs. Do I double up for every input? Can I have 1 input (home) for every axis and the last input wired for all 4 axis (limit)?

Thanks.