Siemens 3RQ3018-2AN08-0AA0 Coupling Relay 110V DC 6A Push-in

The Siemens SIRIUS 3RQ3 series 3RQ3018-2AN08-0AA0 is an ultra-slim coupling relay (output coupler) with a housing only 6.2 mm wide. It couples and electrically isolates signals between controller outputs and field loads. It provides one change-over contact (1 CO) with a 6 A thermal current rating, and output ampacity of 3 A at AC-15 / 250 V and 1 A at DC-13 / 24 V. Safe isolation between the control circuit and the auxiliary circuit is rated up to 300 V—no separate isolating amplifier is needed.

The decisive difference of this model is its 110 V DC coil. Where the control circuit itself runs on high-voltage direct current—non-motoric DC applications such as electrolysis, electromagnets and battery charging, or an existing 110 V DC control bus—this coil connects directly, with no need to step down the voltage for the relay or add an interposing relay. The operating range is 0.7-1.25 × Us (approximately 77-137.5 V), wider than the 24 V versions, giving greater tolerance to voltage sag on the DC bus.

This product is engineered for both industrial and rail duty. Its operating temperature range extends to −40 … +70 °C (versus −25 … +60 °C on the 24 V versions), and it is qualified to DIN EN 61373 category 1 class B for shock and vibration—making it suitable for control circuits on rolling stock. Wiring uses spring-loaded push-in terminals for tool-free termination, holding constant contact pressure under continuous vibration. Power consumption is 0.6 W, the enclosure carries a UL94 V-0 flammability rating, and the relay complies with the RoHS directive (2015-03-25).

The 93 × 6.2 × 72.5 mm housing snaps onto any standard 35 mm DIN rail in any mounting position and requires 0 mm spacing for side-by-side mounting, so dozens can be packed onto a single rail. Mechanical service life reaches 10,000,000 operating cycles.

• 110 V DC coil—connects directly to a high-voltage DC control bus, no step-down or interposing relay required
• Wide 0.7-1.25 × Us operating range (approx. 77-137.5 V)—greater tolerance to DC bus voltage sag
• Rail-qualified shock and vibration—meets DIN EN 61373 category 1 class B for rolling stock applications
• Wide temperature range, −40 … +70 °C—broader than the 24 V versions in the same series
• Spring-loaded push-in terminals—tool-free wiring with constant contact pressure under vibration
• Ultra-slim 6.2 mm width—dozens fit on a single 35 mm DIN rail
• One change-over contact (CO), 6 A thermal current—drives loads directly, no intermediate amplifier required
• 300 V safe isolation between control and auxiliary circuit—removes the need for a separate isolating amplifier
• 4 kV surge voltage resistance and 300 V insulation voltage (overvoltage category III, pollution degree 3)
• UL94 V-0 enclosure flammability rating, RoHS compliant (2015-03-25); 10,000,000 mechanical operating cycles