33919 - Industrial 8-Channel PWM Input Module, Modbus RTU Protocol - Waveshare

Eight-Channel Industrial PWM Acquisition Module

The Waveshare 33919, Modbus RTU PWM Input 8CH model, measures the frequency and duty cycle of eight PWM signals. Values are accessible via an RS485 interface using the Modbus RTU protocol.

Frequency and Duty Cycle Measurement

The eight inputs accept signals from 3.3 to 30 V. The frequency measurement range extends from 400 Hz to 50 kHz with a resolution of 0.01 Hz. The duty cycle is measured from 0 to 100% with a resolution of 0.01%.

Modbus RTU Communication

The RS485 interface supports multiple baud rates from 4,800 to 256,000 bps. The default format is 9,600 bps, no parity, 8 data bits, and 1 stop bit. The Modbus address is configurable from 1 to 255.

Industrial Isolation and Protections

The module integrates power and signal isolation, high-speed optocouplers, TVS protection, a resettable fuse, and a watchdog. These protections enhance resistance to electrical interference.

Power Supply and Mounting

The power supply accepts a DC voltage from 7 to 36 V. The enclosure is designed for 35 mm DIN rail mounting, allowing for compact installation in an industrial cabinet.