Messung SL2004LN5 (NXG)

The Messung SL2004LN5 (NXG) is an industrial Text-based Human Machine Interface (HMI) from the Smartline (Nexgen) series.¹ It is a legacy product widely used in the Indian automation market (Messung was later acquired by Mitsubishi Electric).

This unit is primarily used for displaying machine status, alarms, and allowing operators to enter simple parameters (like timers or counters) into a PLC.

1. Display and Visuals

• Type: Backlit LCD (Liquid Crystal Display).²

   

• Format: 20 Characters x 4 Lines (Total 80 characters displayable).³

   

• Series: NXG (Nexgen) – This indicates it belongs to the “Next Generation” improvement of the original Smartline series, featuring better processing and communication reliability.

2. Physical Interface (Keypad)

Unlike touchscreen HMIs, the SL2004 relies on a membrane keypad for durability in harsh environments:⁴

• Function Keys: Usually features 8 to 16 programmable function keys (F1, F2, etc.) for direct machine commands (e.g., Start, Stop, Reset).

• Numeric Keypad: Dedicated buttons for numbers 0–9 for easy data entry.

• Navigation: Cursor keys (Up, Down, Left, Right) to scroll through menus and alarm lists.

3. Connectivity and Ports

• Communication: Standard serial ports supporting RS-232 and RS-485.⁵

   

• PLC Compatibility: Designed primarily to work with Messung Nexgen 4000/5000 PLCs and Mitsubishi FX Series PLCs.⁶ It also supports various third-party protocols for other brands like Siemens (S7-200) or Allen Bradley.

   

• Programming: Programmed using the SOFTLINE or SL Designer software via a PC serial cable.⁷

   

4. Technical Specifications

5. Common Use Cases

• Process Monitoring: Viewing temperature, pressure, or production counts.

• Fault Diagnostics: Displaying clear text alarm messages (e.g., “Emergency Stop Pressed” or “Motor Overload”).

• Parameter Setting: Changing machine setpoints without needing a computer.