Inputs
HOMEx
The HOME inputs are required for the machine to be able to detect the ‘home’ position.
The home input can be configured into two modes, each mode describes what type of switch or sensor is connected. If the switch or sensor is activated, it means that it will switch either to ground (0V) or to a voltage, in this case, 24V. A switch or sensor that switches to 0 (negative) is called NPN, and a switch or sensor that switches to 24V (positive) is called PNP.
PNP = Input should be ‘HIGH’ (24V) to detect the switch/sensor being activated.
NPN = Input should be ‘LOW’ (0V) to detect the switch/sensor being activated.
Please note, that ALL home inputs are EITHER NPN or PNP. Currently, it is not possible to mix the input types. The software expects one type of input to be used and will not work correctly if the jumpers are set differently.
This mode selection is done via several jumpers:
Each jumper corresponds to an input:
Jumper | Input |
JP6 | HOME1 mode NPN or PNP |
JP7 | HOME2 mode NPN or PNP |
JP8 | HOME3 mode NPN or PNP |
JP9 | HOME4 mode NPN or PNP |
The image below shows how the input operates.
Switching in NPN mode
When in NPN mode the input needs to switch to ground to be activated.
Switching in PNP mode
When in PNP mode the inputs need to switch to +24V to be activated.
DRVALM input
The DRVALM can be used to report problems with the motor driver. There is only a single input, normally the outputs of the motor driver can simply be combined to this input.
The input can have two modes, either NPN or PNP. This means either it will react when this input is switched to ground (NPN), or the input signal goes to the positive power supply (PNP).
This mode can be set via a jumper
The image below shows how the input operates.
All alarm outputs of the motor driver need to be wired together. If the alarm outputs of the drives are open-collector outputs, so that the alarm outputs of all drives can be coupled together, and each output can pull the alarm input low to generate an alarm. The input of the DRVALM input can be set to NPN.
Please note, check that the motor driver ALARM output is truly configured to be ‘open’ if not active.
The image below shows such a setup.
Each drive can generate an alarm that will switch low the DRVALM input, resulting in detection of this alarm.
Make sure you test the alarm input before start to use it.
RUN/PAUSE inputs
The RUN and PAUSE inputs can be used to externally start or stop a job. However, they are also used when you want to connect a wired external pendant. If the software is in JOGWHEEL modus these inputs are used for zeroing the position (START) or selecting the axis (PAUSE).
Using the PAUSE or RUN input is simply connecting a push button to it, with one side connected to GROUND and the other to the input of the board.
In the image below is a schematic of each digital input:
See also chapter “9 Connecting and setting up a wired handwheel” for more info how to use these inputs as part of a wired pendant.
The PAUSE and RUN inputs have a maximum input level of 5V and will be damaged if 24V is applied.
HW-A/HW-B Inputs
The HW-A/HW-B inputs can be used to connect a handwheel for exactly setting the position of an axis or changing the feedrate. The position of the axis can only be changed if the software is in JOGWHEEL modus.
The image below shows how a pendant can be connected to these inputs.
See also chapter “9 Connecting and setting up a wired handwheel” for more info how to use these inputs as part of a wired pendant.
In the image below is a schematic of each digital input:
The HW-A/HW-B inputs have a maximum input level of 5V and will be damaged if 24V is applied.
AN1/AN2 inputs
The analog inputs can have several functions
- Reading external values for control
- Controlling the feedrate
- Selecting an axis or multiplier in a wired pendant application
The analog inputs have an input range of 0-3.3V, applying voltages that exceed this voltage will damage the inputs and even lead to the failure of the controller.
For this application the 3.3V (AVDD) is made available on pin #10 of connector CN2. Do not use this voltage for other applications!
If you want to test this input, a simple 10k potentiometer can be used as shown in the image below.
Using this potentiometer to control the feedrate can be changed in the application setup it should be indicated that an analogue input is used. In this case either ‘Analog 1’ or ‘Analog 2’.
For more info about reading the input please have a look at the manual about writing macros and reading I/O’s.
For more info about how to use the analog inputs for a wired pendant have a look at chapter “9 Connecting and Setting up a wired handwheel”.
EXT-ERROR input
The EXT-ERROR input can be used for indicating any external ERROR has occurred. The behavior of this input can be indicated in the setup of the application.
The input can have two modes, either NPN or PNP. This means either it will react when this input is switched to ground (NPN), or the input signal goes to the positive power supply (PNP).
This mode can be set via jumper JP13
The image below shows how the input operates
E-STOP input
The E-STOP input is used for indicating an EMERGENCY. The CNC720 is equipped with hardware features that can shut down the outputs if an E-STOP occurs, this is in addition to the software behavior in case of an E-STOP condition.
The hardware E-STOP functionality shuts down the following outputs:
- DIRx/STEPx/ENABLEx
- TOOLON
- COOL1
- COOL2
- PWM/0-10V (Configurable)
- AUX01 (configurable)
The board features a connector to which the E-STOP switch needs to be connected.
Please note that jumper JP4 needs to be removed if an external switch is used.
This pin is also available on connector CN2 on pin #12.
The E-STOP inputs need to be connected with a ‘normally closed’ (NC) switch. As a result, if the E-STOP cable has a broken wire this will automatically trigger an E-STOP condition.
The figure below shows a basic schematic of how this works
It’s important to understand that the external E-STOP is by default disabled through bypass jumper JP4. With the jumper mounted the user will be able to use the board if no external switch is applied.
The software behavior of the E-STOP can be defined in the software setup. The hardware behavior of the E-STOP is through several jumpers. These jumpers are indicated below
If you don’t want to use the hardware shutdown, please remove the jumper that enables this feature.
PWM/0-10V Behavior during E-STOP
The PWM/0-10V output will by default be shutdown if an E-STOP event occurs, if the application needs this signal to remain the same the jumper can be set in the opposite position, in that case the output signal will not be shutdown in case of an E-STOP event.
AUX01 Behavior during E-STOP
The AUX01 output will by default be shut down if an E-STOP event occurs, if the application needs this signal to remain the same the jumper can be set in the opposite position, in that case the output signal will not be shut down in case of an E-STOP event.
SPINDLE-X input
The SPINDLE-X input can be used to connect an external sensor that indicates the rotation of the spindle or used in case of tapping when used in a lathe application.
The SPINDLE-X has a maximum input level of 5V and will be damaged if 24V is applied.
Below the input circuit is shown for the SPINDLE-X input
To use the SPINDLE-X the input signal needs to switch to ground to be active. The image below shows this.
The SPINDLE-X input has a maximum input level of 5V and will be damaged if 24V is applied.
PROBE input
The probe input has a dual use. It can be used for the tool measurement, measuring the height of a tool, or it can be used for probing an object. If both tools are used, they can be connected together to this input. However, make sure that they both use the same kind of output signal.
The input can have two modes, either NPN or PNP. This means either it will react when this input is switched to ground (NPN), or the input signal goes to the positive power supply (PNP).
This mode can be set via a jumper.
The image below shows how the input operates
