How to use the Modbus Interface of XY6020L Digital Programmable Power Supply Module
Since I couldn't find any documentation on the net, I've compiled this document with the necessary information to make use of the serial interface and Modbus protocol.
The module is basically very similar to the DPS5020, but it has a extended Modbus register set, as it supports more features.
The data sheet promises an input voltage range of up to 70V and an output capabilty up to 60V and max. 20A.
It can operate in headless mode (whithout operator panel) and is significantly cheaper than DPS5020.
Additionally it has a timer measuring the output 'on' time, and counters for cumulated mAh and mWh during an active output session.
Thus the module would be an ideal candidate for battery charging or solarpanel tracking projects and experiments.
Unfortunately I observed a severe issue with the transition from CC to CV mode.
While battery charging, the module sometimes fails to reduce the charging current when battery reaches the programmed CV voltage level.
Looks like the regulator is locked in CC mode and the output (battery) voltage raises way above the CV voltage.
This is imho a dangerous malfunction and I cannot recommend to use it for battery charging.
You have been warned ...
Here is a detailed picture of the wiring to a Modbus adapter (HW-519).
Of course, such an adapter is only requried for a real Modbus setup. The interface will also work on plain TTL level, e.g. to talk with an MCU.
