The EL1502 EtherCAT Terminal is an up/down counter and transmits the counter value in an electrically isolated form to the higher-level automation device. When used as a single-channel up/down counter (32-bit), the pulse is set via the clock input; the counting direction is specified via the U/D input. Furthermore, the input can also be used as a gate input for triggering the counter. In 2-counter mode, two separate counters are available (Clock and Clock1 inputs), which can be parameterized as up or down counters. The signal state of the inputs and outputs is indicated by light emitting diodes. Both outputs are switched according to the counter state, so that they can be used as fast control signals for field devices. The EL1502 device supports the distributed clocks function. This means the counter can be read at constant intervals (DC accuracy << 1 µs).

Special features:

• suitable for fast counting tasks with counting frequencies up to 100 kHz
• one up and down counter or two separate up or down counters
• synchronized operation through distributed clocks XFC technology possible

https://www.beckhoff.com/vi-vn/products/i-o/ethercat-terminals/el1xxx-digital-input/el1502.html