UniOP BKDR-16 human-machine interface

4.4 Historical Events and Formulas

The historical event list can record 256 events with timestamps, which are sourced from the hardware clock/calendar. This RTC uses an independent backup battery (usually CR2032) that can continue to run for at least one year after the main power supply is disconnected. For GMP or ISO traceability systems that require traceability of operation records (such as who modified the set temperature at what point), this function is indispensable.

The recipe function provides 16KB of non-volatile storage space, which can be divided into multiple independent recipe tables. Each recipe table can store a set of process parameters, such as pressure, speed, and temperature range of the injection molding machine. The operator selects the recipe number through the keyboard, downloads it to the PLC with one click, or uploads and saves the current PLC value as a new recipe. 16KB may not seem large, but it is enough to accommodate hundreds of floating-point numbers or thousands of integer parameters.

4.5 Security and Peripherals

The password protection function supports multi-level permissions at the operator level, engineer level, and administrator level, with different screens and operable function keys visible at different levels. In addition, BKDR-16 also retains a standard parallel or serial printer interface that can hard copy alarms, events, and current images to compatible industrial printers - which remains a compliance requirement in the chemical and pharmaceutical industries that require paper record archiving.

Typical Engineering Application Scenarios

Scenario 1: Monitoring and renovation of old air compressor units

A certain factory has three Ingersoll Rand air compressors produced in the 1990s, each with only a simple indicator panel, no communication interface, only dry contact signals (operation, fault, temperature switch) and 4-20mA analog signals (exhaust pressure, oil temperature). Engineers use BKDR-16 as the central operating station: analog signals are connected to PLCs (such as Siemens S7-1200 or domestic compatible modules), and dry contact signals are directly isolated by optocouplers and connected to the digital input expansion of BKDR-16 (through external I/O modules via communication ports). Use a macro editor to convert pressure and temperature into actual engineering values, and draw trend curves on a 320 × 240 screen. The operator can achieve start stop and parameter switching of three units through 14 function keys, without the need to learn complex touch screen menus.

Scenario 2: Operating terminal outside the explosion-proof area

In the petrochemical plant area, operators must remotely monitor the temperature of the reactor and the status of the agitator in a safe area. Due to the presence of flammable gases on site, conventional touch screens cannot be used (capacitive screens cannot be operated with gloves, and explosion-proof touch screens are expensive). BKDR-16 is equipped with an explosion-proof installation box, and all operations are completed through physical buttons. The monochrome LCD is still clear and readable under strong outdoor light. The UniNET client function of the device simultaneously reads two different PLC systems (one responsible for the reactor and the other for the tank area), and displays key data on the same page, avoiding operators from running back and forth between two computers.

6、 Common troubleshooting and on-site maintenance guide

Based on years of on-site maintenance experience and the hardware characteristics of BKDR-16, the following are the six most common types of fault phenomena, cause analysis, and handling steps. Be sure to disconnect the 24V power supply before performing any maintenance operations.

Fault 1: The screen has no display, but the power indicator light is on

Possible reasons:

LCD contrast potentiometer drifts or is mistakenly set to the lowest.

Backlight inverter damaged (monochrome LCD usually has CCFL backlight).

The wiring between the motherboard and LCD is loose or oxidized.

Troubleshooting steps:

Press the preset "contrast+" function key on the keyboard (usually configured on a certain function key) or enter the system menu to adjust the contrast.

Observe whether there is a faint halo at the edge of the screen in a dark environment. If not, it indicates a backlight malfunction.

Disassemble and inspect the cable plug, clean the gold finger with an eraser, and re insert it tightly.

Fault 2: Communication with PLC is intermittent or completely disconnected

Possible reasons:

The communication parameters (baud rate, data bits, checksum) do not match.

The RS-485 bus is not connected to a terminal resistor or the A/B lines are reversed.

Using the wrong physical interface (e.g. selecting RS-232 mode but actually wiring RS-485).

For the 20 mA current loop mode: the loop power supply is missing or the current loop polarity is reversed.

Troubleshooting steps:

Use a serial port monitoring tool (such as a PC with a serial port debugging assistant) to intercept the message sent by BKDR-16 and confirm if there is any data output.

Connect BKDR-16 and PLC separately point-to-point (excluding bus interference), gradually increasing the number of nodes.