1769-ASCII Communication Module for ASCII Compatible Devices
Product Introduction
The 1769-ASCII module connects your CompactLogix or MicroLogix 1500 controller to ASCII compatible devices. Typical applications include barcode readers in factory automation. This module provides two individually isolated serial ports. Each port can operate simultaneously with different configurations. Furthermore, you can set each port to alternating mode or dual simultaneous mode.
Technical Specifications
The 1769-ASCII draws 425mA at 5Vdc from the backplane. Maximum power dissipation is 2.13 Watts, and thermal dissipation reaches 7.3 BTU/hr. Isolation voltage is 30V continuous.
For serial communication, the 1769-ASCII offers two full duplex ports (RS232 and RS422) plus two half duplex ports (RS485). Port 1 supports RS232 and RS422. Port 2 supports RS485 independently. The serial input voltage signal ranges from 3V to 25Vdc (active) and -3V to -25Vdc (inactive) with respect to signal ground.
Additionally, the module includes RTS/CTS hardware handshaking. Serial port status indicators cover TX FIFO overflow, RX FIFO overflow, RX parity error, handshake error, and new data flag. Configuration uses 31 words, while input uses 108 words.
Power Supply Distance and Compatibility
The 1769-ASCII has a power supply distance rating of four modules. Therefore, install it no more than four modules away from the CompactLogix power supply. The module is backplane powered, so no external power supply is needed.
Compatible power supplies include 1769-PA2, 1769-PB2, 1769-PA4, and 1769-PB4. In a MicroLogix 1500 system, place the 1769-ASCII beside the base unit or next to another 1769 Compact module.
Mechanical and Environmental Ratings
This module measures 87 x 34 x 118 mm (3.43 x 1.34 x 4.65 in.) and weighs 0.18 kg (0.40 lb). Operating temperature ranges from 0°C to 60°C (32°F to 140°F). Storage temperature spans -40°C to 85°C (-40°F to 185°F). Relative humidity is 5–95% non‑condensing.
Moreover, the 1769-ASCII withstands 5g vibration at 10–500 Hz. Operating shock is 30g, and non‑operating shock is 50g. Use the recommended shielded cable Belden 8761 for best performance.
Mounting and Installation
You can mount the 1769-ASCII on a DIN rail or directly on a panel. The module uses two DB‑9 male serial ports for physical connections. First, install the module in an available slot. Next, configure each port individually for your ASCII devices.
The serial ports are isolated from the backplane. This isolation prevents ground loops and electrical noise. Remember that the 1769-ASCII must sit within four modules of the power supply. Exceeding this distance may cause unreliable operation.
Packaging List
Shipping via FedEx, UPS, or DHL.
Frequently Asked Questions (FAQ)
1. What controllers work with the 1769-ASCII?
The 1769-ASCII works with CompactLogix controllers and MicroLogix 1500 systems.
2. Can both ports run at the same time?
Yes. Both ports operate simultaneously with independent configurations. One port can use RS232 while the other uses RS485.
3. What is the current draw of the 1769-ASCII?
It draws 425mA at 5Vdc. Maximum power dissipation is 2.13 Watts.
4. Do I need an external power supply for this module?
No. The 1769-ASCII is backplane powered. It draws all necessary power from the CompactLogix or MicroLogix system.
5. What cable is recommended for the 1769-ASCII?
Use Belden 8761 shielded cable for reliable communication. This cable reduces electrical noise and improves signal integrity.
