UniOP ePAD03/04 Human Computer Interface

UniOP ePAD03 and ePAD04 Compact Human Machine Interface: From Technical Features to Field Operations

In industrial automation projects, the cost of human-machine interface (HMI) is often directly proportional to its functional complexity. However, a large number of simple control tasks (such as small packaging machines, temperature control boxes, and simple tooling tables) do not require high-resolution color touch screens, but rather value the reliability of physical buttons, wide compatibility of communication protocols, and extremely low economic barriers. The ePAD03 and ePAD04 launched by UniOP are products targeting this niche market. They offer a much higher functional density than products in the same price range at an entry-level price, and are clearly positioned as an ideal alternative to the successful MD00 series models. In addition, some models support an extended operating temperature range (suffix -00B6 and -00B7) and can operate stably in extreme environments such as -20 ℃ to 60 ℃. This article will comprehensively analyze ePAD03 and ePAD04 from multiple dimensions such as hardware architecture, communication capability, software functionality, installation size, and common troubleshooting, and provide engineering recommendations for smooth migration from the MD00 series.

Product positioning and model differentiation

EPAD03 and ePAD04 are the smallest and lowest cost graphical human-machine interfaces in the UniOP family. Both use monochrome graphic LCDs, equipped with 4 user programmable function keys and 7 system keys, and support access to fieldbus (Profibus DP, CANopen, DeviceNet, Interbus) and Ethernet through optional modules. The core differences are mainly reflected in the display resolution and real-time clock (RTC) configuration:

EPAD03: Equipped with a 120 × 32 pixel monochrome LCD, active display area of 70 × 21 mm, supports hardware RTC (battery backup, CR2430 lithium battery), user memory 512KB Flash, recipe memory 16KB, 256 event lists, and 1024 alarms.

EPAD04: The hardware platform is essentially the same as ePAD03, but does not include a hardware real-time clock (RTC). The event list and recipe memory functions are marked as "-" in the original table, indicating that there may be limitations at the software level. Its display resolution is 4 lines x 20 characters in text mode (based on a 120 x 32 pixel dot matrix of the same size).

In short, ePAD03 is a fully functional version (with timestamp recording capability), while ePAD04 is the ultimate cost cutting version for pure display/input tasks that do not require time tracing. Both models have three sub model suffixes:

-0046: Standard operating temperature 0~50 ℃

-00B6: Extended working temperature 0~60 ℃

-00B7: Expand the working temperature range to a wider range (storage temperature -20~60 ℃, working temperature may be as low as -20 ℃? The original text is not clear, but the suffix is different)

When engineers choose, if they need to record the precise time of alarm and event occurrence (such as for ISO or GMP traceability), they must use the ePAD03 series; If only used for real-time data display and parameter settings, ePAD04 can further save costs.

Detailed explanation of hardware architecture and interfaces

2.1 Display and Interaction

EPAD03/ePAD04 adopts a 120 × 32 pixel monochrome LCD, which can display text of 4 lines × 20 characters. It can also display bar charts, numerical values, and simple icons through scalable fonts and dynamic graphic objects. Although the resolution is low, it is sufficient for most parameter monitoring and setting tasks. The screen is LED backlit, and the contrast is adjusted through software.

The physical buttons include:

4 user programmable function keys: support slide in legends, users can print paper labels and insert them next to the keys for easy function definition (such as start, stop, menu).

7 system keys: usually including directional keys, confirm keys, exit keys, etc., used for navigation menus and numerical input.

5 user programmable LED indicator lights: can be mapped to the bit status in the PLC, used to display motor operation, faults, etc.

4 system LEDs: display basic status such as power and communication.

This fully physical button design makes the ePAD series more reliable than touchscreens in glove operated, oily environments, or situations with strong vibrations.

2.2 Power Supply and Electrical Parameters

Supply voltage: 18~30 VDC (nominal 24V DC)

Current consumption: 0.25 A @ 24 VDC (typical power consumption 6W)

Fuse: Automatic recovery type (self recovering fuse)

Protection level: IP65 front panel (dustproof and water-resistant)

Weight: Approximately 1 kg

2.3 Mechanical dimensions and installation openings

According to technical data:

Panel size (width x height): 149 x 109 mm (5.86 "x 4.29")

Hole size (width x height): 136 x 96 mm (5.35 "x 3.78")

Installation depth: 53 mm (2.08 ")

This compact size allows it to easily replace the MD00 series (which typically uses similar openings) and is also suitable for installation on control cabinet doors or operation boxes with limited space.