MB-LI-4 Lo 4-channel pulse counter, Modbus RTU

Why choose the MB-LI-4 Lo?

The MB-LI-4 Lo is a four-channel pulse counter designed to count AC/DC signals generated by external devices. The Lo variant features low-voltage counting inputs.

What does this mean in practice?

• There are 4 independent counting inputs.
• The voltage range of signals at the counting inputs is 6–30 V AC/DC.
• The maximum counting frequency is 100 Hz.
• You can set the conversion factor and read the scaled value.
• It is possible to select the signal edge to which the counter responds.
• A frequency filter allows the pulse detection method to be configured.
• The counter status is retained after the supply voltage is lost.
• The counting input can also function as a digital input (DI).
• Data is made available via RS-485 Modbus RTU.

Principle of operation of the MB-LI-4 Lo pulse counter

The MB-LI-4 pulse counter is a 4-channel unidirectional counter. Each channel is independent and counts pulses according to its individual settings. The results are presented as the number of pulses and a rescaled value in the range from 0 to ~4.29 billion. The counter has a software function that allows the counter status of each channel to be reset independently. Upon reaching the maximum number of pulses (overflow), the counter automatically resets and starts counting from 0. The module features configurable options for counting pulses with a low (0 V) or high (V+) signal, as well as with a rising or falling edge.

Additionally, the counting input can be used as a digital input (DI) with the option to read its status.
Reading the count of pulses, scaled values, and setting all counting, communication and data exchange parameters is carried out via the RS-485 port using the MODBUS RTU communication protocol. The application of supply voltage is indicated by the green U LED lighting up. Correct data exchange between the module and another device is indicated by the yellow Tx LED lighting up.

NOTE!
An external control voltage is always required to trigger the input. If the module’s supply voltage is used for this purpose, it will result in the loss of galvanic isolation between the control inputs and the power supply and communication circuits.

MB Config
The programme allows you to test-read values and configure the transducer’s communication and configuration parameters.



Communication between the module and a PC via theCN-USB-485 USB converter
Free software.