Centroid Community CNC Support Forum

You can get solid-shaft encoders, in 1/4", 6mm, 8mm etc., from Automation Direct for less than $200 each.

For example, TRDA-2E2500VD, TRD-S2500-VD, and TRDA-20R1N2500VD.

polaraligned wrote: ↑Tue May 11, 2021 5:10 pm CG is "Case Ground" per spec sheet. You don't need to connect anything to it to get the encoder to work. Just ignore it.

The only connection to the encoder "G" should be pin 2 of the DB9 connector.

Are you sure you are counting the pin numbers correctly on the DB9 connector? The pin numbers are usually raised numbers on the solder side and often difficult to see easily.

When you have the unit powered up with the Centroid, do you get +5v between the encoder V terminal and the G terminal? If that is correct, use your meter to carefully measure between the A and /A, and the B and /B terminals at the encoder and make sure you have at least 3 volt difference between those.

Backing up a little bit.

Definitely counting the pin numbers correctly.

Powered up, on X I get 4.864 from G to V. From A to A/ I get 2.152 and from B to B/ I get 2.151 (not a typo, they are the same)
Y is 4.874 A to A/ is 2.152 B to B/ is 62.4
Z is 4.869 A to A/ is 2.081 B to B/ is 2.081 (not a typo, they are the same)

cncsnw wrote: ↑Fri May 14, 2021 8:43 pm Can you measure the current draw of your old encoders? Maybe they are overloading the 5VDC supply.

Though if that were the case, I would expect the Allin1DC unit to shut down, since that is also its logic power....

No idea how to measure that.

I ran spindlebenchtest.cnc and input all of the voltages as requested.

Then got to step 1 Encoder Test on page 32 again and got absolutely no change in values on the screen.

No idea how to measure that.

In a nutshell, you set your meter to measure DC milliAmps. This usually requires moving the red test lead from one socket to another, as well as choosing the correct dial setting.

Then you disconnect the +5VDC supply wire to the encoder; connect the +5VDC supply wire to the red test lead; and connect the black test lead to the encoder where the +5V wire used to be.

The meter is now part of the supply circuit, and will tell you how much current is flowing into the encoder.

If you have never done this before, you should read the instructions for your particular meter.

When you are done using the meter to measure current, it is critically important that you put the red test lead back in the Volts/Ohms socket before you again try to measure voltage with it.

cncsnw wrote: ↑Sun May 16, 2021 12:19 am

No idea how to measure that.

In a nutshell, you set your meter to measure DC milliAmps. This usually requires moving the red test lead from one socket to another, as well as choosing the correct dial setting.

Then you disconnect the +5VDC supply wire to the encoder; connect the +5VDC supply wire to the red test lead; and connect the black test lead to the encoder where the +5V wire used to be.

The meter is now part of the supply circuit, and will tell you how much current is flowing into the encoder.

If you have never done this before, you should read the instructions for your particular meter.

When you are done using the meter to measure current, it is critically important that you put the red test lead back in the Volts/Ohms socket before you again try to measure voltage with it.

Thank you for that lesson! Results were similar on all three encoders. X ranged from 1.23 mA to 1.51 (rotating the shaft by hand out of curiosity), Y ranged from 1.36 to 1.53, and Z ranged from 1.12 to 1.42.

For future reference, I would imagine that it's standard practice to shut everything down before disconnecting/reconnecting wires (which is what I did).

Your red lead should be in the V-ohm-ma input, not the 10A input. You will get a more accurate reading on low currents. Your encoders should be pulling about 150 ma according to the datasheet- which is a pretty decent draw. Recheck the current to see if it is close to specification.

Try testing with only one encoder connected to the power supply to lighten up the load on the supply line.

Measure each output to common. You should be able to turn the shaft and have the value change just like on the bench test, but this time with the encoder attached to the machine. When one is high level, then check the other for a low output without turning the shaft. If you fail that test, throw the encoders against a wall and get new ones. The Automation Direct encoders are less than $100 each which is a bargain.

I misunderstood because you mentioned moving the red lead twice in your description to me.

Tomorrow's another day and I'm beat from catching up on yard/house work.

I'm not convinced that the encoders are bad yet as they were working fine before and I am getting erratic results from the ALLINONE. One time I fire it up, I get all three encoders have errors. Then the next time, only one or two.

According to the instructions, if I can get to "MDI", that indicates that all errors have been cleared. I've been there a few times, but still get no movement on the set up page when it says to rotate the encoder shaft.

Please don't get frustrated with me. I have a long way to go.

Your setup is good other than just taking the red lead at the meter and plugging it into the meter jack that is open in the pictures. In other words, don't use the 10A jack because that is for higher currents. The V-ohm-mA jack is the lower current range and you probably will get a better reading on actual current. The LED inside the encoder is going to draw in the range of 20 mA alone.

Yep, got that, thanks! I'll give it another try when time allows.