[jimbogrif]

I need help. I have four proximity switches (APS4-12s-e-d), a new G540, a 48vdc power supply for the motors, and a separate 12vdc power supply for the proximity switches. The motors are working fine but I can't get the proximity switches to work. I use them to home the machine in X and Y and as limit switches in Mach3. I'm very confused with all of the posts in this forum. Is there a simple solution to the wiring of these switches or won't they work with the G540? I've been using these proximity switches for a long time with a breakout board and separate G202 Drives. I'm hoping that they'll work with the G540 because of cost and simplification. Thanks in advance for the help.

[Richards]

The APS4-12S-E-D is an NPN sensor that requires 10-30VDC input to operate correctly. You'll need to connect the Brown wire to the "+" voltage (10 to 30VDC). The Blue wire is connected to the G540's GND. The Black wire is connected to one of the four input pins. When the sensor "sees" its target, it will pull its Input LOW. I've used the APS4-12M-E-D with my G540 with excellent results.

[doorknob]

The APS4-12S-E-D is an NPN sensor that requires 10-30VDC input to operate correctly. You'll need to connect the Brown wire to the "+" voltage (10 to 30VDC). The Blue wire is connected to the G540's GND. The Black wire is connected to one of the four input pins. When the sensor "sees" its target, it will pull its Input LOW. I've used the APS4-12M-E-D with my G540 with excellent results.

Just curious - does the internal NPN transistor in those switches have an open collector, or does the blue output lead have an internal pull-up resistor to the positive supply?

[Richards]

Look at wiring diagram #1 at http://www.automationdirect.com/stat...oxrectaps4.pdf. That is all the information provided for the proximity sensor.

Buy one and experiment, then you'll know whether it meets your requirements.

I always provide ~12VDC for proximity sensors. My G540 uses 48VDC, which is much too high for the sensors. A +12VDC "wall-wart" power supply will give you anywhere from 10-16V. That's close enough for the proximity sensors. They can handle voltages from 10V to 30V.

[morestuff]

Traditionally these NPN outputs were intended to be true open collector, but
recently many vendors have started putting a mild pull-up (10K ohms seems
popular) into these devices. The argument was that people needed to be
able to see if they were working by just connecting a volt meter to the
output. The unfortunate consequence is that for some sensitive circuits
the pull-up can cause problems.

[Richards]

The schematic for the G540 shows that the inputs must sink current through an optocoupler that is in series with a 200 ohm resistor. The data sheet for the proximity sensor tells us that the proximity sensor can sink 100mA. In the applications that I design, I require at least 10mA through a typical optocoupler to make the optocoupler work. The proximity sensor can sink 10X that much.

When I get stuck with a circuit that doesn't seem to work properly, I grab some similar parts from my "junk box" (or run down to Radio Shack) and play with the parts until I can see where I've made a mistake.

[Mariss Freimanis]

I Googled "APS4-12s-e-d" and pulled-up the specifications .pdf for this switch. Here's what you do:

1) Get the "NPN" version of this switch.
2) Connect your proximity switch to the power supply you intend to use for it (+24VDC to "1", GND to "3").
3) Connect proximity switch term "1" to the G540 term 12.
4) Connect proximity switch term "4" to the G540 input you plan to use (INPUT 1, 2, 3 or 4).

That's all there is to it.

Mariss

[dsnellen]

I Googled "APS4-12s-e-d" and pulled-up the specifications .pdf for this switch. Here's what you do:

1) Get the "NPN" version of this switch.
2) Connect your proximity switch to the power supply you intend to use for it (+24VDC to "1", GND to "3").
3) Connect proximity switch term "1" to the G540 term 12.
4) Connect proximity switch term "4" to the G540 input you plan to use (INPUT 1, 2, 3 or 4).

That's all there is to it.

Mariss

Mariss,

I am researching how to use the Hamlin 55110-3H-02-A Hall Effect Senors as honing switches. Thinking this post would lead to the answer my question, I also Googled "APS4-12s-e-d" to follow your discussion. The "APS4-12s-e-d" has three wires like the "55110-3H-02-A". What did you mean by term 1,3 & 4? In my plan, I connect the "55110-3H-02-A" Blue wire to G540 input 1, 2, 3, or 4. Using a combination of resistors ( Voltage Divider Calculator) to reduce the 48 volt input to 12 volts on the Red wire and the GND to the Black wire. Do you or any one else see a problem with this?

[dsnellen]

Mariss,

I am researching how to use the Hamlin 55110-3H-02-A Hall Effect Senors as honing switches. Thinking this post would lead to the answer my question, I also Googled "APS4-12s-e-d" to follow your discussion. The "APS4-12s-e-d" has three wires like the "55110-3H-02-A". What did you mean by term 1,3 & 4? In my plan, I connect the "55110-3H-02-A" Blue wire to G540 input 1, 2, 3, or 4. Using a combination of resistors ( Voltage Divider Calculator) to reduce the 48 volt input to 12 volts on the Red wire and the GND to the Black wire. Do you or any one else see a problem with this?

For historical purposes, here is what I did. Using the Voltage Divider Calculator mentioned above, I used two 1k resistors to drop the 48 volts power supply to 24 volts. Then fed that into a Radio Shack 7805 Voltage Regulator which gives me a clean and constant 5 VDC output. The Voltage Regulator output gnd was wired to pins 6-9 on the DE 9 female plug. The +5 VDC output was wired to pin 5 of the DE 9 female plug. The Hamlin 55110-3H-02-A Hall Effect Senors red wire is connected to pin 5 and the black wire to pin 6 - 9. The blue wire is connected to pin 1 to 4 corresponding to input 10, 11, 12 or 13. It works, its simple and does not require an external VDC transformer/voltage source.

Note: All limit/home switches can use the same DE9 pin 5 for the 5 VDC and any of the DE9 pins 6-9 for GND. The Voltage Regulator isn't necessary. The Hamlin 55110 can handle an input of 24 VDC. I had the regulator on hand so I used it. +5VDC is also handy for using lasers.

Dave