The 3UG3012-1AL50 operates on a 3x230 V AC supply (line-to-line), common in small three-phase networks where no neutral is available. The asymmetry setting of 5–20% lets you trip the relay when phase voltages deviate beyond that threshold — useful for detecting a blown fuse or an unbalanced motor load before it causes damage. The 1 W power consumption means the relay generates negligible heat inside the panel, so no derating for adjacent devices. The IP20 protection class means the relay is touch-safe but not protected against moisture ingress — it belongs inside a sealed enclosure, not on the machine frame.
Siemens 3UG3012-1AL50 Monitoring Relay, 3-Phase Voltage, 230
MPN3UG3012-1AL50
Siemens SIRIUS discontinued type monitoring relay, 3UG3012-1AL50, 3-phase voltage monitoring, asymmetry 5-20%, 1W, AC 3x230V 50/60Hz, screw connection.
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Jul 2026
Specifications
| Parameter | Value |
|---|---|
| Product line / brand name | SIRIUS |
| Parameter | Value |
|---|---|
| Ingress protection (IP rating), wired | IP20 |
| Parameter | Value |
|---|---|
| Fastening method | snap-on mounting |
| Parameter | Value |
|---|---|
| During operation | -25 ... +60 °C |
| Reference code acc. to IEC 81346-2 | K |
| Number of poles for main current circuit | 3 |
Product details
Frequently asked questions
What replaces the 3UG3012-1AL50?
The official replacement is the Siemens 3UG4614-1BR20. It provides the same 3-phase voltage monitoring function (phase loss, asymmetry, undervoltage) in a similar 45 mm housing with screw terminals.
What are the key ratings of the 3UG3012-1AL50?
It is a 3-phase voltage monitoring relay for AC 3x230V 50/60Hz, with adjustable asymmetry 5-20%, 1 W power consumption, IP20, snap-on mounting, and screw connection. Operating temperature range is -25 to +60 °C.
MPN
3UG3012-1AL50