The Siemens 3UG4632-2AA30 is a SIRIUS voltage monitoring relay with digital setting, designed to keep a sharp eye on supply rails in control panels. It measures AC or DC voltage from 10 V up to 600 V and flags both overvoltage and undervoltage conditions, with a relative repeat accuracy of 1%. That means when you set a threshold, it won't drift — you can trust the trip point shift under 1% of full scale across the operating temperature range.
The measurable voltage range covers 10 to 600 V AC/DC, so it handles common 24 VDC control circuits, 120 VAC line monitoring, and 480 VAC motor feeds without needing a separate PT. The rated supply voltage is 24 V AC/DC (50/60 Hz) — that's the coil power, not the monitored voltage. It draws 1 A at 24 V, which is the contact rating for the output relay; at 125 V the contact is rated 0.2 A, and at 250 V it drops to 0.1 A. These are resistive-load numbers; inductive loads need derating or snubbing. The relay offers both auto-reset and external reset capability, with the initial value set at 0.85 and full-scale value at 1.15 — these are the hysteresis bands around the threshold. For a 24 V monitored line, the relay would pick up at 85% (20.4 V) and drop out at 115% (27.6 V) of the set point, adjustable via the digital interface. Mounting is snap-on DIN rail (22.5 mm wide), and the relay can be installed in any orientation — no derating for sideways or upside-down mounting. IP20 protection means it's for use inside a cabinet only; not rated for washdown or dust ingress. The LCD display shows the measured value and settings, making commissioning quicker — no need to probe with a meter to confirm the threshold.