How to measure the current?

[starCNC]

Hey all,
I just received my controller today. I not sure how to measure the current of it. I made a diagram of if, let me know if it is wrong. Is "#" means positive?

[starCNC]

I am using powermaxII P21 model, 1.75 bipolar series.

[ynneb]

You will blow a fuse or the board if you do what is in the photo.

To measure current you must place the multimeter in series with the motor.

Series is like a daisy chain. Do you know whatt series is?

When In amp mode, just think of the two wires as one continuous wire. The only difference is that one continous wire diverts in and out of you Multi meter. Essentially it is still one wire though.

I dont know about your card but assume you ahve drawn the outputs as correct. Anyway here is how to connect a series circuit.

[starCNC]

I just got the Xylotex driver, i need to limit the curent going to the motor. 1.7amp is required for the motor

[ynneb]

I just got the Xylotex driver, i need to limit the curent going to the motor. 1.7amp is required for the motor

Then you will need to put a resistor in series with the motor. You will need to know the voltage of your power supply, and the resistance of your motor, to work out what size resistor you will need. Its been a while since I have done this sort of calculation (its an easy calculation from memory) but if you post both those numbers I am sure someone here can tell you what size resistor you need.

[marvinstov]

Actually you don't need any external resistors on the Xylotex. It is adjustable using the pot shown in the drawing just above the heat sink. For 1.7 amps the adjustment should read 1.44 x 1.7amps = 2.448 volts, measured from a ground point on the board to a pad with a hole in it labeled "TPZ, TPX or TPY" depending on the axis you are adjusting (These are located just out of view at the top of your picture). The corresponding resistors are labled "VRZ, VRX AND VRY" Set the meter for volts and measure between ground (black lead on the meter) and TPZ for the Z axis and adjust the pot" VRZ" until your meter reads 2.448 volts and it will be set for 1.7 amps. This can be adjusted without power to VBB.

Marv

[marvinstov]

Here is a picture for the measuring points on the Xylotex board. They will be the same for each axis, one pot and one test pad with a hole in it.

[starCNC]

how ground hole you show me didn't work, the hole right below(G) it works. thanks for your help

[marvinstov]

Glad to be of help.

Marv

[starCNC]

Marvinstov,
i have one more question, is "#" means + on the diagram?

[marvinstov]

If you are referring to the terminal block where the motor connects, it is just a naming convention. There are four terminals , two for each phase of the motor. They could have been names 1A, 1B, 2a, 1b just as easily. When you connect the motors to these terminals, make sure you connect the two wires from the same phase terminals on the block. Example : connect one phase to the ZB# and ZB terminals and one phase to the ZA# and ZA terminals. Which way you connect them does not matter at this point. When you have it running if the motor is turning the wrong way, you can switch two wires of the same phase to revers the motor direction or do it in the software (Turbocnc, other programs may not allow this). In other words, if it runs the wrong way change either ZB and ZB# or ZA and ZA# wires but NOT both. Just do not change both pairs, you will end up with the motor not changing directions.

What else?

Marv

[marvinstov]

Oops,

"They could have been names 1A, 1B, 2a, 1b just as easily"

Should read: "They could have been names 1A, 1B, 2a, 2b just as easily"

Sorry, should proof read better.

Marv