A Modular Datalogger and Slow-Control Platform for Physics Experiments with Time-Series Telemetry and Web Dashboards

Abstract: We present a NIM 2U slow-control system designed for continuous monitoring of environmental and facility parameters during data taking in nuclear physics experiments. The architecture integrates a base controller board with eight channels for PT100/PT1000 probes and up to three plug-in extension boards, each providing SMA connections on the front panel. All boards adopt a 16-bit SAR ADC with an external 2.5 V reference, yielding an LSB of 38.15 uV and ensuring metrological uniformity across heterogeneous channel types. The operating range for PT100/PT1000 probes spans -200 degrees Celsius to 300 degrees Celsius, with a design accuracy at the 1 percent level. The system includes modules dedicated to standard industrial signals 4--20 mA and 0--10 V and a module for current measurement in the 500 nA--100 uA range with automatic gain range selection. The software chain publishes time series to Graphite and provides visualization through Grafana over Ethernet. A complete quantitative characterization of stability and accuracy is ongoing and will be reported in a subsequent work.