GP477R Engineering Installation

Attention: The 12th and 13th pins are idle and must not be connected to any wires, otherwise it may damage the printer interface.

In practical engineering, due to the fact that modern printers are mostly USB or network interfaces, the frequency of use of this port is extremely low. If data recording is required, it is recommended to use a serial port external micro printer or forward the data to the upper computer through PLC.

AUX auxiliary interface (input/output)

The AUX interface is a 15 pin D-sub female socket that provides the following very practical external control and monitoring signals, which are very useful for integrating safety emergency stop circuits and equipment status indicators.

6.1 Pin List

Pin signal function description

1 TSW0 touch switch output (8-bit, TSW0~TSW7)

2 TSW1 

3 TSW2 

4 TSW3 

5 TSW4 

6 TSW5 

7 TSW6 

8 TSW7 

9 RUN mode output: ON when GP is running; OFF when standby or power is off

10 ALARM alarm output: Conducted when a fatal hardware or software error occurs

11 BUZZ buzzer output: Follow the action of GP internal buzzer

12 DC24V output common terminal (DC24V side)

13 AIN-C input common terminal (DC24V side)

14 AOUT-C output common terminal (GND)

15 RESET reset input (low pulse effective)

6.2 Main application scenarios

Touch switch output (TSW0~7): When the user presses the specified touch switch on the screen, the corresponding transistor output will turn on. It can be directly used to control external indicator lights or relays, achieving "physical devices can be operated on the screen". These outputs are in the form of open collector and require an external pull-up resistor or DC load.

RUN output: can be used to light up a "running" indicator light when GP is running, or to interlock with PLC.

ALARM output: When GP detects serious faults such as screen memory verification errors or system errors, this output will be activated, thereby cutting off the main contactor or triggering the central alarm system.

Buzzer output: It can be connected in parallel with an external high-power buzzer to synchronously drive the external speaker when the GP emits a button sound or alarm sound.

Reset input (RESET): Short circuit the RESET pin (low level active) to AIN-C to reset the GP software, which is equivalent to powering on again. GP that can be used for remote reset of crashes.

When wiring, please distinguish the common terminal: use AOUT-C (GND) for the output circuit and AIN-C (DC24V) for the input circuit. We recommend using the OMRON XM2A-1501 plug, with the same screw specifications as the serial port M2.6.

Anti interference and signal line wiring

As a touch screen, GP477R is highly susceptible to electromagnetic interference from strong electrical devices such as frequency converters and contactors, resulting in communication interruption, touch misoperation, or display flickering. The following measures must be strictly implemented:

Separation of signal lines and power lines: All I/O signal lines (including serial ports, AUX, printers) must be routed separately from AC power lines, motor lines, and inverter output lines, with a minimum spacing of 20cm. If crossing is necessary, it should be done vertically instead of parallel.

Use shielded cables: Serial and AUX cables should use cables with total shielding and twisted pair structure. The shielding layer should be grounded at a single point at the GP end (connected to the FG terminal) and suspended at the opposite end to avoid ground current.

Grounding independence: The FG terminal of GP cannot be connected in series with the ground wire of the power equipment, and must be separately led to the grounding copper bar of the control cabinet. The grounding resistance should be less than 100 Ω, and if possible, it should be less than 10 Ω.

Surge protection: Connect a varistor (such as S14K275) in parallel at the power input end, or use a socket with filtering function.

Communication line length limit: RS-232C distance ≤ 15 meters, RS-422 ≤ 1200 meters (actual affected by baud rate). When exceeding the recommended distance, please use a repeater.

Summary of Safety Operations and Maintenance Suggestions

8.1 Safety principles that must be absolutely followed

No live plugging or unplugging: Before any operation of connecting or disconnecting cables, the GP power supply must be cut off. Otherwise, it may burn the port or cause electric shock.

Unauthorized disassembly is prohibited: GP has high-voltage circuits and lithium batteries (used for clock backup) inside. If lithium batteries are replaced incorrectly, there is a risk of explosion, and users cannot replace the batteries themselves. Please contact an authorized repair station when replacement is required.

External emergency stop: Virtual buttons on the touch screen must not be used for safety emergency stop functions. An independent mechanical emergency stop switch must be installed separately, and the main circuit cannot be directly controlled through GP.

Communication fault safety design: The control system should be able to detect communication interruptions between GP and PLC (such as through heartbeat signals) and put the machine into a safe state in case of a fault, rather than blindly executing the last instruction.