What it is and what it monitors
The Siemens 3UG5742-1CW30 is a digital monitoring relay from the SIRIUS 3UG5 family, designed to measure current, active current, voltage, power factor (cos-phi), and active power. It operates on a supply voltage of 24 to 240 V AC/DC at 50/60 Hz and handles monitoring circuits up to 690 V AC/DC and up to 15 A directly. The relay includes Bluetooth connectivity for wireless parameterization and data readout, plus two changeover contacts for alarm or trip outputs.
Key ratings and what they mean for fit
The 690 V AC/DC rating covers most industrial control voltages up to 480/600 V class systems with headroom. The 15 A direct-current path means you can wire the monitored circuit straight through the relay without an external current transformer for loads up to that level. The 24-240 V AC/DC supply range accepts any common control voltage from 24 VDC to 240 VAC, simplifying panel wiring — one relay works across different cabinet voltages without a separate power supply module. On-delay and tripping delay are adjustable from 0.1 to 999.9 s, giving you time grading for coordinated fault response.
Sourcing and procurement note
As an active, current-production item, the 3UG5742-1CW30 is sourced through standard Siemens distribution channels. For BOM-line commitment or urgent line-down replacement, submit an RFQ with your required quantity and target delivery window. The relay ships individually (packaging quantity 1) in dimensions 127 x 111 x 38 mm.