The wheel needs a +5V power supply, and outputs a slightly lower voltage on A+/B+/A-/B-. One step of the wheel goes through a full cycle. This is not a regular switch, so no connection can be measured.
It is a rotary encoder with grey code. Need to check 4 bit or 2 bit. Some arduino Librarys are available Demotape (talk)
Emergency Stop
This is a standart Mushroom Knot
Inside are 2 simple normally closed switch.
one is connected to the control unit to stop the program
the second one is connected with the power switch so if pressed the Power for motors and spindle will be switched off ( power for the control unit stay on)
Spindle
Connector Pins = Cable
1 = 1
2 = 2
3 = 3
4 = PE
Cable = controller side
Cable 1 = U
Cable 2 = V
Cable 3 = W
PE Cable = E
LED
A red LED, 20mA standard current drive.
Selection Switches
These switches are connected through the "Enable" button on the left. No signal is received unless the button is pressed.
The X, Y, Z and 4 pins are connected to COM when the respective axis is selected, and the enable switch pressed.
The x1, x10 and x100 pins are connected to COM when the respective speed is selected, and the enable switch pressed.