Siemens Monitoring Relay, 3 Phase, DPDT, DIN Rail, 120/690 V ac

This monitoring relay is a digitally adjustable network monitor designed for line supervision in three-phase AC installations. It checks phase sequence, phase loss, asymmetry, frequency and both over- and undervoltage within industrial supply networks, and provides relay switching to protect downstream equipment in control panels mounted on a 35mm DIN rail.

• 0.1–30 s adjustable response delay for tailored start-up protection
• Monitors 3 x 90–690 V AC and 15–70 Hz for wide voltage/frequency ranges
• Two changeover contacts delivering 3A switching for control circuits
• Auto-reset and adjustable N-conductor recognition for flexible operation
• Detects phase asymmetry and phase failure to prevent motor stress
• Screw terminals accepting up to 4 mm² conductors for secure connections

• Suitable for monitoring supply integrity to three-phase motors
• Ideal for integration into machine control panels on DIN rails
• Used for protective supervision of distribution boards and feeders
• Can be used for frequency-sensitive equipment protection
• Suitable for installations requiring adjustable voltage window detection

It accepts AC control supply from 120–690 V across 50/60 Hz with an operating range factor from 0.85 to 1.1.

Relative metering precision is 3% with a digital-display accuracy of ±1 digit and temperature drift of 0.001%/°C.

The unit offers galvanic isolation between inputs and outputs and surge resistance up to 6kV, with conductor-to-conductor surge rating to 1kV.

Typical mechanical life is 10 million cycles and electrical endurance around 100,000 cycles at AC-15/230 V.

Use gL/gG fuses rated 6 A or an MCB type C at 1 A for protecting both NO and NC contact circuits.