Z-Axis and Z-Axis IO PCB

The Z-axis is composed of a motor carriage, an extrusion, end caps, a sliding cover, a status light, and an IO Printed Circuit Board (Rev 2 version of the ZIO, “ZIO2”). The Z motion drive consists of a timing belt reduction and main drive belt attached to the Z stage. The Z motor includes a fail-safe brake that can be manually released by pressing a button on the side of the ZIO2 Board.

The ZIO2 PCB serves as a connector board for motor and encoder signals and provides 8 isolated user digital input and 8 isolated user digital output signals. It also supports a robot status light, and an optional power supply and connectors for the arm mounted Ethernet camera and ring light option. For I/O control, this board is connected to the robot’s controller by an RS485 serial line that allows the I/O to be scanned with a nominal period of 4 milliseconds.

Figure 34-169 illustrates the position of each of the key connectors on the board.


Contact with electrical power can cause serious personal injury or death. A motor connector that provides a bus voltage of 320 VDC is positioned near the ZIO2. As such, accessing this board represents a high-risk Disconnect the main AC power to the robot before accessing this board.

Electrical Shock Hazard

Contact with electrical power can cause serious personal injury or death. A motor connector that provides a bus voltage of 320 VDC is positioned near the ZIO2. As such, accessing this board represents a high-risk

Disconnect the main AC power to the robot before accessing this board.

Figure 34-169: Position of Key Connectors on Board

In Table 34-124, each of the connectors is briefly described. For application interfaces, such as the digital output signals, pin assignments are described in detail in subsequent tables.

Table 34-124: Connectors
Connector	Description
Abs Encoder Bat Jumpers	On newer boards, these jumpers are present and are factory set depending upon whether the Z-axis has hall effect sensors or an absolute encoder that requires battery power.
Brake Release Button / Output	The Brake Release Output is wired to the fail-safe brake on the Z-axis motor. This brake prevents the axis from falling when power is off. Normally, this brake is automatically controlled by the system software. If the Brake Release Button is pressed, the brake can be manually released so long as power is provided to the robot's controller.
Camera Power / Light Power	If the optional Arm Mounted Camera Kit is purchased, these connectors provide power to the camera and the camera's ring light. The camera power is always available whenever the robot's controller is powered on. The ring light power can be turned on and off via software control. Two identical connectors are provided to simplify wiring.
Digital Inputs / Digital Outputs	These provide 8 optically isolated user input and 8 optically isolated user output signals. These signals are available to interface to tooling and sensors mounted on the end of the robot. These signals are described in detail below.
LED1 (Activity / Error)	Green - Blinks fast (about 10 Hz) when the ZIO2 is not communicating with the robot's controller. Blinks slowly (about 1 Hz) during normal communication. Red - Off at initial power-up and during normal communications. On if communications is lost after being established.
LED2 (Camera light)	Green - Tracks the state of the camera ring light power. Red - No currently used.
Power Status Light	This connects to an LED mounted in the top of the Z-axis cover. (See below for more information.)
RS485 Daisy Chain	The RS485 interface is a multi-drop high speed serial interface that permits the robot controller to operate the digital input and output signals on the ZIO2 board. Two identical connectors are provided to permit the RS485 signals to be daisy-chained to other RS485 devices mounted on the end of the robot.
Theta Encoder To Harness/Motor	These are two pass through connectors that interface the Theta (4th) axis encoder to the appropriate signals in the robot harness. The Theta encoder internal harness connector should be plugged into the "To Harness" board connector. If a Theta axis is present, its encoder should be plugged into the "To Motor" connector.
Z Encoder To Harness/Motor	These are two pass through connectors that interface the Z (3rd) axis encoder to the appropriate signals in the robot harness. The Z-axis encoder internal harness connector should be plugged into the "To Harness" board connector. The Z-axis encoder should be plugged into the "To Motor" connector.

The 8 isolated digital input and 8 isolated digital output signals provided on the ZIO2 are intended for interfacing to tooling and sensors mounted on the end of the robot or for other general application needs. These DIO signals are in addition to those available on the X-axis Facilities Panel of the robot. These signals are provided in two 16-pin connectors (Figure 34-170).

Figure 34-170: Sixteen-Pin Connector

The 8 digital input signals are configured as "sinking" (Figure 34-171), that is, the external equipment must supply a 5 VDC to 24 VDC voltage to indicate a logical high value or must allow it to float to no voltage for a logical low. For convenience, 24 VDC is supplied on the digital input signal connector. These inputs are compatible with "sourcing" (PNP) sensors.

Figure 34-171: Sinking Input

The 8 digital output signals are configured as "sourcing" (Figure 34-172), that is, the external equipment must pull-down an output pin to ground and the ZIO2 pulls this pin to 24 VDC when the signal is asserted as true. Each output signal can supply a maximum of 100mA. For convenience, ground pins are supplied on the digital output signal connector. These outputs are compatible with "sinking" (NPN) devices.

Figure 34-172: Sourcing Output

The pin assignments for these two connectors are defined in Table 34-125 and Table 34-126 along with the signal numbers used to reference these signals from GPL and the part number for the required hardware plugs

As of November 2008, the ZIO board's Digital Input 8 failed the CE 10 volts per meter Radiated RF Immunity test. Therefore, until this has been corrected, for CE applications, only ZIO inputs bits 1-7 may be used

Table 34-125: Pin Assignments with Digital Input
Pin	GPL Signal Number	Description
1	10033	Digital Input 1
2	10037	Digital Input 5
3	10034	Digital Input 2
4	10038	Digital Input 6
5	10035	Digital Input 3
6	10039	Digital Input 7
7	10036	Digital Input 4
8	10040	Digital Input 8
9 to 16		24 VDC
User Plug Part No		Amp 746285-3 or Molex 22-55-2161 or Molex 90142-0016. For the Molex plugs, use Molex pins 16-02-0103 and Molex crimp tool 63811-1000.
High Flex Cable		A high flex cable should be used to ensure long life. We recommend 3M Round Conductor High Flex Life Flat Cable, 28 AWG stranded, PVC, 3319/16 or Amphenol Spectra-Flex high flex life flat cable 843-191-2811-016.

Table 34-126: Pin Assignments with Digital Ouput
Pin	GPL Signal Number	Description
1	33	Digital Output 1
2	37	Digital Output 5
3	34	Digital Output 2
4	38	Digital Output 6
5	35	Digital Output 3
6	39	Digital Output 7
7	36	Digital Output 4
8	40	Digital Output 8
9 to 16		Ground
User Plug Part No		Amp 746285-3 or Molex 22-55-2161 or Molex 90142-0016. For the Molex plugs, use Molex pins 16-02-0103 and Molex crimp tool 63811-1000.
High Flex Cable		A high flex cable should be used to ensure long life. We recommend 3M Round Conductor High Flex Life Flat Cable, 28 AWG stranded, PVC, 3319/16 or Amphenol Spectra-Flex high flex life flat cable 843-191-2811-016.

There are two four-pin connectors (Figure 34-173) that provide power for an Ethernet camera and camera ring light if the Arm Mounted Camera Kit is installed.

Figure 34-173: Four-Pin Connector

The pin assignments for these connectors are defined inTable 34-127 along with the part number for the required plug type. Two connectors provide identical signals as a wiring convenience.

Table 34-127: Pin Assignments
Pin	GPL Signal Number	Description
1		12 VDC for powering camera, 1.25 A total current is shared between two connectors.
2		Ground
3	8039	9 VDC for powering ring light. Enabled and disabled via a dedicated system IO signal or via the robot ZIO control panel in the Web Operator Interface. 1 A total current is shared between two connectors.
4		Ground
User Plug Part No		AMP 794617-4. Use an AMP 91501-1 hand crimp tool and AMP 1-794610-2 sockets for wiring to the plug.

If the yellow Outer Link status LED is configured as normally shipped from the factory, Table 34-128 describes how to interpret each light pattern.

Table 34-128: Light Pattern
Status LED	Description
Continuously Off	AC power off or processor crashed. Either the AC power is off or the processor has crashed due to a system hardware or software error. If the processor has crashed, it may be executing the firmware debugger, dBug.
Continuously On	Booting sequence. AC power is on and the firmware and software are being loaded. The LED begins blinking when the system is up and running. Process crashed. If the LED turns on continuously after it has been blinking, the processor has crashed due to a system hardware or software error. The processor may be executing the firmware debugger, dBug.
Blinks 1 times per second	Normal operation, motor power off.
Blinks 4 times per second	Normal operation, motor power on.
Blinks 8 times per second	Processor overheating, motor power off. There are five minutes to save any programs or data. After five minutes, the processor will shut down and it will need to be rebooted.